497 1 d264819d497.htm MASSMUTUAL SELECT FUNDS MASSMUTUAL SELECT FUNDS

MASSMUTUAL SELECT FUNDS

MassMutual RetireSMARTSM Funds

Supplement dated September 26, 2016 to the

Prospectus dated February 1, 2016

This supplement provides new and additional information beyond that contained in the Prospectus and any previous supplements. It should be retained and read in conjunction with the Prospectus and any previous supplements.

Effective September 27, 2016, the following information replaces similar information found on page 4 for the MassMutual RetireSMARTSM Conservative Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .12%        .22%        .32%        .42%        .42%        .32%        .32%   

Acquired Fund Fees and Expenses

     .52%        .52%        .52%        .52%        .52%        .52%        .52%   

Total Annual Fund Operating Expenses(1)

     .64%        .74%        .84%        .94%        1.19%        1.09%        1.34%   

Expense Reimbursement

     (.17%     (.17%     (.17%     (.17%     (.17%     (.17%     (.17%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .47%        .57%        .67%        .77%        1.02%        .92%        1.17%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year-to-date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .47%, .57%, .67%, .77%, 1.02%, .92%, and 1.17% for Classes I, R5, Service,


  Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 48       $ 181       $ 334      $ 776  

Class R5

   $ 58       $ 213       $ 388      $ 897  

Service Class

   $ 68       $ 245       $ 443      $ 1,016  

Administrative Class

   $ 79       $ 276       $ 497      $ 1,133  

Class A

   $ 673       $ 909       $ 1,171      $ 1,916  

Class R4

   $ 94       $ 323       $ 578      $ 1,308  

Class R3

   $ 119       $ 402       $ 712      $ 1,592  

Effective September 27, 2016, the following information replaces similar information found on pages 5 and 6 for the MassMutual RetireSMARTSM Conservative Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     28.8

MM Select Equity Asset (NTI)

     12.2

Select Diversified Value (Brandywine Global/Loomis Sayles)

     0.3

Select Fundamental Value (Wellington Management)

     0.3

Select Large Cap Value (Barrow Hanley/Huber Capital Management)

     0.2

Premier Disciplined Value (Barings)

     1.8

Select Focused Value (Harris)

     1.6

Select Fundamental Growth (Wellington Management)

     0.3

Select Blue Chip Growth (T. Rowe Price/Loomis Sayles)

     0.6

Select Growth Opportunities (Sands Capital/Jackson Square)

     0.2

Premier Disciplined Growth (Barings)

     1.7

Select Mid-Cap Value (American Century/Systematic)

     0.9

Select Small Cap Value Equity (Wellington Management/Barrow Hanley)

     0.7

Select Small Company Value (Federated Clover/T. Rowe Price/Invesco)

     0.3

Select Mid Cap Growth Equity II (T. Rowe Price/Frontier)

     0.7

Select Small Cap Growth Equity (Wellington Management/OFI Global)

     0.5

Oppenheimer Real Estate (OFI Global Asset Management)

     0.4

Select Diversified International (J.P. Morgan)

     0.4

Select Overseas (J.P. Morgan/MFS/Harris)

     2.3


Premier International Equity (OFI Global)

     1.1

Premier Strategic Emerging Markets (OFI Global)

     2.0

Oppenheimer Developing Markets Fund (OFI Global Asset Management)

     0.4

Fixed Income Funds

     69.4

MM Select Bond and Income Asset (NTI)

     20.7

Premier Short-Duration Bond (Barings)

     9.8

Premier Inflation-Protected and Income (Barings)

     3.2

Premier Core Bond (Barings)

     17.3

Select Total Return Bond (MetWest)

     7.3

Select Strategic Bond (Western Asset)

     6.2

Premier High Yield (Barings)

     3.2

Oppenheimer International Bond Fund (OFI Global Asset Management)

     1.1

Barings Global Floating Rate (Barings)

     0.7

Other Funds

     1.8

DFA Commodity Strategy (DFA)

     1.8

Effective September 27, 2016, the following information replaces similar information found on page 12 for the MassMutual RetireSMARTSM Moderate Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .07%        .17%        .27%        .37%        .37%        .27%        .27%   

Acquired Fund Fees and Expenses

     .59%        .59%        .59%        .59%        .59%        .59%        .59%   

Total Annual Fund Operating Expenses(1)

     .66%        .76%        .86%        .96%        1.21%        1.11%        1.36%   

Expense Reimbursement

     (.12%     (.12%     (.12%     (.12%     (.12%     (.12%     (.12%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .54%        .64%        .74%        .84%        1.09%        .99%        1.24%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.


(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .54%, .64%, .74%, .84%, 1.09%, .99%, and 1.24% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 55       $ 195       $ 352       $ 807   

Class R5

   $ 65       $ 227       $ 406       $ 927   

Service Class

   $ 76       $ 258       $ 461       $ 1,046   

Administrative Class

   $ 86       $ 290       $ 515       $ 1,163   

Class A

   $ 680       $ 922       $ 1,187       $ 1,943   

Class R4

   $ 101       $ 337       $ 596       $ 1,337   

Class R3

   $ 126       $ 415       $ 729       $ 1,621   

Effective September 27, 2016, the following information replaces similar information found on pages 13 and 14 for the MassMutual RetireSMARTSM Moderate Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     56.3

MM Select Equity Asset (NTI)

     23.7

Select Diversified Value (Brandywine Global/Loomis Sayles)

     1.1

Select Fundamental Value (Wellington Management)

     1.0

Select Large Cap Value (Barrow Hanley/Huber Capital Management)

     0.9

Premier Disciplined Value (Barings)

     2.5

Select Focused Value (Harris)

     1.9

Select Fundamental Growth (Wellington Management)

     1.0

Select Blue Chip Growth (T. Rowe Price/Loomis Sayles)

     1.2


Select Growth Opportunities (Sands Capital/Jackson Square)

     0.8

Premier Disciplined Growth (Barings)

     2.5

Select Mid-Cap Value (American Century/Systematic)

     2.1

Select Small Cap Value Equity (Wellington Management/Barrow Hanley)

     1.5

Select Small Company Value (Federated Clover/T. Rowe Price/Invesco)

     0.6

Select Mid Cap Growth Equity II (T. Rowe Price/Frontier)

     1.6

Select Small Cap Growth Equity (Wellington Management/OFI Global)

     1.1

Oppenheimer Real Estate (OFI Global Asset Management)

     0.7

Select Diversified International (J.P. Morgan)

     0.9

Select Overseas (J.P. Morgan/MFS/Harris)

     5.3

Premier International Equity (OFI Global)

     2.4

Premier Strategic Emerging Markets (OFI Global)

     3.0

Oppenheimer Developing Markets Fund (OFI Global Asset Management)

     0.7

Fixed Income Funds

     41.1

MM Select Bond and Income Asset (NTI)

     11.7

Premier Short-Duration Bond (Barings)

     4.9

Premier Inflation-Protected and Income (Barings)

     1.9

Premier Core Bond (Barings)

     9.9

Select Total Return Bond (MetWest)

     4.1

Select Strategic Bond (Western Asset)

     3.5

Premier High Yield (Barings)

     3.3

Oppenheimer International Bond Fund (OFI Global Asset Management)

     1.2

Barings Global Floating Rate (Barings)

     0.8

Other Funds

     2.6

DFA Commodity Strategy (DFA)

     2.6

Effective September 27, 2016, the following information replaces similar information found on page 20 for the MassMutual RetireSMARTSM Moderate Growth Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

    

Class

A

     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   


Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .08%        .18%        .28%        .38%        .38%        .28%        .28%   

Acquired Fund Fees and Expenses

     .66%        .66%        .66%        .66%        .66%        .66%        .66%   

Total Annual Fund Operating Expenses(1)

     .74%        .84%        .94%        1.04%        1.29%        1.19%        1.44%   

Expense Reimbursement

     (.15%     (.15%     (.15%     (.15%     (.15%     (.15%     (.15%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .59%        .69%        .79%        .89%        1.14%        1.04%        1.29%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .59%, .69%, .79%, .89%, 1.14%, 1.04%, and 1.29% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 60       $ 216       $ 391       $ 899   

Class R5

   $ 70       $ 248       $ 446       $ 1,018   

Service Class

   $ 81       $ 279       $ 500       $ 1,136   

Administrative Class

   $ 91       $ 311       $ 554       $ 1,253   

Class A

   $ 685       $ 942       $ 1,224       $ 2,025   

Class R4

   $ 106       $ 358       $ 635       $ 1,425   

Class R3

   $ 131       $ 436       $ 768       $ 1,707   


Effective September 27, 2016, the following information replaces similar information found on pages 21 and 22 for the MassMutual RetireSMARTSM Moderate Growth Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     79.6

MM Select Equity Asset (NTI)

     33.6

Select Diversified Value (Brandywine Global/Loomis Sayles)

     2.2

Select Fundamental Value (Wellington Management)

     1.9

Select Large Cap Value (Barrow Hanley/Huber Capital Management)

     1.8

Premier Disciplined Value (Barings)

     2.0

Select Focused Value (Harris)

     1.5

Select Fundamental Growth (Wellington Management)

     2.0

Select Blue Chip Growth (T. Rowe Price/Loomis Sayles)

     2.2

Select Growth Opportunities (Sands Capital/Jackson Square)

     1.5

Premier Disciplined Growth (Barings)

     2.0

Select Mid-Cap Value (American Century/Systematic)

     2.7

Select Small Cap Value Equity (Wellington Management/Barrow Hanley)

     2.4

Select Small Company Value (Federated Clover/T. Rowe Price/Invesco)

     1.0

Select Mid Cap Growth Equity II (T. Rowe Price/Frontier)

     2.0

Select Small Cap Growth Equity (Wellington Management/OFI Global)

     1.7

Oppenheimer Real Estate (OFI Global Asset Management)

     0.9

Select Diversified International (J.P. Morgan)

     1.3

Select Overseas (J.P. Morgan/MFS/Harris)

     8.2

Premier International Equity (OFI Global)

     3.7

Premier Strategic Emerging Markets (OFI Global)

     4.1

Oppenheimer Developing Markets Fund (OFI Global Asset Management)

     0.9

Fixed Income Funds

     17.1

MM Select Bond and Income Asset (NTI)

     3.6

Premier Short-Duration Bond (Barings)

     0.9

Premier Inflation-Protected and Income (Barings)

     0.5

Premier Core Bond (Barings)

     2.7

Select Total Return Bond (MetWest)

     1.2

Select Strategic Bond (Western Asset)

     1.0

Premier High Yield (Barings)

     4.6

Oppenheimer International Bond Fund (OFI Global Asset Management)

     1.5

Barings Global Floating Rate (Barings)

     1.1

Other Funds

     3.3

DFA Commodity Strategy (DFA)

     3.3


Effective September 27, 2016, the following information replaces similar information found on page 28 for the MassMutual RetireSMARTSM Growth Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .22%        .32%        .42%        .52%        .52%        .42%        .42%   

Acquired Fund Fees and Expenses

     .68%        .68%        .68%        .68%        .68%        .68%        .68%   

Total Annual Fund Operating Expenses(1)

     .90%        1.00%        1.10%        1.20%        1.45%        1.35%        1.60%   

Expense Reimbursement

     (.26%     (.26%     (.26%     (.26%     (.26%     (.26%     (.26%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .64%        .74%        .84%        .94%        1.19%        1.09%        1.34%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .64%, .74%, .84%, .94%, 1.19%, 1.09%, and 1.34% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the


initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 65       $ 252       $ 464       $ 1,075   

Class R5

   $ 76       $ 283       $ 518       $ 1,192   

Service Class

   $ 86       $ 315       $ 572       $ 1,308   

Administrative Class

   $ 96       $ 346       $ 626       $ 1,423   

Class A

   $ 689       $ 974       $ 1,290       $ 2,182   

Class R4

   $ 111       $ 393       $ 705       $ 1,593   

Class R3

   $ 136       $ 470       $ 837       $ 1,870   

Effective September 27, 2016, the following information replaces similar information found on pages 29 and 30 for the MassMutual RetireSMARTSM Growth Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     92.3

MM Select Equity Asset (NTI)

     38.3

Select Diversified Value (Brandywine Global/Loomis Sayles)

     3.3

Select Fundamental Value (Wellington Management)

     2.9

Select Large Cap Value (Barrow Hanley/Huber Capital Management)

     2.7

Premier Disciplined Value (Barings)

     0.6

Select Focused Value (Harris)

     1.6

Select Fundamental Growth (Wellington Management)

     3.1

Select Blue Chip Growth (T. Rowe Price/Loomis Sayles)

     3.4

Select Growth Opportunities (Sands Capital/Jackson Square)

     2.3

Premier Disciplined Growth (Barings)

     0.6

Select Mid-Cap Value (American Century/Systematic)

     3.1

Select Small Cap Value Equity (Wellington Management/Barrow Hanley)

     2.9

Select Small Company Value (Federated Clover/T. Rowe Price/Invesco)

     1.2

Select Mid Cap Growth Equity II (T. Rowe Price/Frontier)

     2.3

Select Small Cap Growth Equity (Wellington Management/OFI Global)

     2.0

Oppenheimer Real Estate (OFI Global Asset Management)

     0.9

Select Diversified International (J.P. Morgan)

     1.5

Select Overseas (J.P. Morgan/MFS/Harris)

     9.3

Premier International Equity (OFI Global)

     4.2

Premier Strategic Emerging Markets (OFI Global)

     4.8

Oppenheimer Developing Markets Fund (OFI Global Asset Management)

     1.1

Fixed Income Funds

     4.1

MM Select Bond and Income Asset (NTI)

     0.9

Premier Short-Duration Bond (Barings)

     0.2

Premier Inflation-Protected and Income (Barings)

     0.2

Premier Core Bond (Barings)

     0.7


Select Total Return Bond (MetWest)

     0.3

Select Strategic Bond (Western Asset)

     0.3

Premier High Yield (Barings)

     0.9

Oppenheimer International Bond (OFI Global Asset Management)

     0.4

Barings Global Floating Rate (Barings)

     0.2

Other Funds

     3.6

DFA Commodity Strategy (DFA)

     3.6

Effective September 27, 2016, the following information replaces similar information found on page 36 for the MassMutual RetireSMARTSM In Retirement Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
    

Service

Class

    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
   

Service

Class

   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .26%        .36%        .46%        .56%        .56%        .46%        .46%   

Acquired Fund Fees and Expenses

     .56%        .56%        .56%        .56%        .56%        .56%        .56%   

Total Annual Fund Operating Expenses(1)

     .82%        .92%        1.02%        1.12%        1.37%        1.27%        1.52%   

Expense Reimbursement

     (.27%     (.27%     (.27%     (.27%     (.27%     (.27%     (.27%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .55%        .65%        .75%        .85%        1.10%        1.00%        1.25%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .55%, .65%, .75%, .85%, 1.10%, 1.00%, and 1.25% for Classes I, R5, Service,


  Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 56       $ 225       $ 419       $ 980   

Class R5

   $ 66       $ 257       $ 474       $ 1,098   

Service Class

   $ 77       $ 288       $ 528       $ 1,215   

Administrative Class

   $ 87       $ 320       $ 582       $ 1,330   

Class A

   $ 681       $ 950       $ 1,249       $ 2,097   

Class R4

   $ 102       $ 367       $ 662       $ 1,502   

Class R3

   $ 127       $ 445       $ 794       $ 1,781   

Effective September 27, 2016, the following information replaces similar information found on page 37 for the MassMutual RetireSMARTSM In Retirement Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     33.9

MM Select Equity Asset (NTI)

     14.0

Fixed Income Funds

     63.9

MM Select Bond and Income Asset (NTI)

     19.0

Premier Short-Duration Bond (Barings)

     9.9

Premier Inflation-Protected and Income (Barings)

     9.0

Premier Core Bond (Barings)

     11.2

Select Total Return Bond (MetWest)

     5.7


Effective September 27, 2016, the following information replaces similar information found on page 43 for the MassMutual RetireSMARTSM 2010 Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .23%        .33%        .43%        .53%        .53%        .43%        .43%   

Acquired Fund Fees and Expenses

     .57%        .57%        .57%        .57%        .57%        .57%        .57%   

Total Annual Fund Operating Expenses(1)

     .80%        .90%        1.00%        1.10%        1.35%        1.25%        1.50%   

Expense Reimbursement

     (.27%     (.27%     (.27%     (.27%     (.27%     (.27%     (.27%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .53%        .63%        .73%        .83%        1.08%        .98%        1.23%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed . 53%, .63%, .73%, .83%, 1.08%, .98%, and 1.23% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the


initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 54       $ 219       $ 408       $ 956   

Class R5

   $ 64       $ 251       $ 463       $ 1,074   

Service Class

   $ 75       $ 282       $ 517       $ 1,191   

Administrative Class

   $ 85       $ 314       $ 571       $ 1,307   

Class A

   $ 679       $ 944       $ 1,239       $ 2,076   

Class R4

   $ 100       $ 360       $ 651       $ 1,479   

Class R3

   $ 125       $ 438       $ 784       $ 1,759   

Effective September 27, 2016, the following information replaces similar information found on page 44 for the MassMutual RetireSMARTSM 2010 Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     41.2

MM Select Equity Asset (NTI)

     17.9

Fixed Income Funds

     56.6

MM Select Bond and Income (NTI)

     17.2

Premier Short-Duration Bond (Barings)

     6.7

Premier Inflation-Protected and Income (Barings)

     7.6

Premier Core Bond (Barings)

     10.4

Select Total Return Bond (MetWest)

     5.3

Effective September 27, 2016, the following information replaces similar information found on page 51 for the MassMutual RetireSMARTSM 2015 Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   


Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .29%        .39%        .49%        .59%        .59%        .49%        .49%   

Acquired Fund Fees and Expenses

     .59%        .59%        .59%        .59%        .59%        .59%        .59%   

Total Annual Fund Operating Expenses(1)

     .88%        .98%        1.08%        1.18%        1.43%        1.33%        1.58%   

Expense Reimbursement

     (.32%     (.32%     (.32%     (.32%     (.32%     (.32%     (.32%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .56%        .66%        .76%        .86%        1.11%        1.01%        1.26%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .56%, .66%, .76%, .86%, 1.11%, 1.01%, and 1.26% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 57      $ 237      $ 445      $ 1,044  

Class R5

   $ 67      $ 269      $ 499      $ 1,162  

Service Class

   $ 78      $ 300      $ 553      $ 1,278  

Administrative Class

   $ 88      $ 332      $ 607      $ 1,393  

Class A

   $ 682      $ 961      $ 1,273      $ 2,154  

Class R4

   $ 103      $ 378      $ 687      $ 1,563  

Class R3

   $ 128      $ 456      $ 819      $ 1,841  


Effective September 27, 2016, the following information replaces similar information found on page 52 for the MassMutual RetireSMARTSM 2015 Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     46.2

MM Select Equity Asset (NTI)

     19.9

Fixed Income Funds

     51.7

MM Select Bond and Income (NTI)

     14.9

Premier Short-Duration Bond (Barings)

     5.6

Premier Inflation-Protected and Income (Barings)

     6.9

Premier Core Bond (Barings)

     10.2

Effective September 27, 2016, the following information replaces similar information found on page 59 for the MassMutual RetireSMARTSM 2020 Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   


Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .05%        .15%        .25%        .35%        .35%        .25%        .25%   

Acquired Fund Fees and Expenses

     .62%        .62%        .62%        .62%        .62%        .62%        .62%   

Total Annual Fund Operating Expenses(1)

     .67%        .77%        .87%        .97%        1.22%        1.12%        1.37%   

Expense Reimbursement

     (.11%     (.11%     (.11%     (.11%     (.11%     (.11%     (.11%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .56%        .66%        .76%        .86%        1.11%        1.01%        1.26%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .56%, .66%, .76%, .86%, 1.11%, 1.01%, and 1.26% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 57      $ 199      $ 358      $ 820  

Class R5

   $ 67      $ 231      $ 413      $ 940  

Service Class

   $ 78      $ 262      $ 467      $ 1,059  

Administrative Class

   $ 88      $ 294      $ 521      $ 1,176  

Class A

   $ 682      $ 926      $ 1,193      $ 1,955  

Class R4

   $ 103      $ 341      $ 602      $ 1,350  

Class R3

   $ 128      $ 419      $ 735      $ 1,633  


Effective September 27, 2016, the following information replaces similar information found on page 60 for the MassMutual RetireSMARTSM 2020 Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     59.5

MM Select Equity Asset (NTI)

     25.1

Select Overseas (J.P. Morgan/MFS/Harris)

     5.5

Fixed Income Funds

     37.8

MM Select Bond and Income (NTI)

     10.6

Premier Inflation-Protected and Income (Barings)

     5.2

Premier Core Bond (Barings)

     6.3

Effective September 27, 2016, the following information replaces similar information found on page 67 for the MassMutual RetireSMARTSM 2025 Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   


Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
   

Class

R5

    Service
Class
   

Admini-

strative
class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .16%        .26%        .36%        .46%        .46%        .36%        .36%   

Acquired Fund Fees and Expenses

     .64%        .64%        .64%        .64%        .64%        .64%        .64%   

Total Annual Fund Operating Expenses(1)

     .80%        .90%        1.00%        1.10%        1.35%        1.25%        1.50%   

Expense Reimbursement

     (.25%     (.25%     (.25%     (.25%     (.25%     (.25%     (.25%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .55%        .65%        .75%        .85%        1.10%        1.00%        1.25%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .55%, .65%, .75%, .85%, 1.10%, 1.00%, and 1.25% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 56      $ 222      $ 411      $ 959  

Class R5

   $ 66      $ 254      $ 466      $ 1,077  

Service Class

   $ 77      $ 285      $ 520      $ 1,194  

Administrative Class

   $ 87      $ 317      $ 574      $ 1,310  

Class A

   $ 681      $ 947      $ 1,242      $ 2,078  

Class R4

   $ 102      $ 364      $ 654      $ 1,482  

Class R3

   $ 127      $ 441      $ 787      $ 1,762  


Effective September 27, 2016, the following information replaces similar information found on page 68 for the MassMutual RetireSMARTSM 2025 Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     69.7

MM Select Equity Asset (NTI)

     28.2

Select Overseas (J.P. Morgan/MFS/Harris)

     6.8

Fixed Income Funds

     27.4

MM Select Bond and Income Asset (NTI)

     6.4

Effective September 27, 2016, the following information replaces similar information found on page 75 for the MassMutual RetireSMARTSM 2030 Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative

Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
    Admini-
strative
Class
    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .05%        .15%        .25%        .35%        .35%        .25%        .25%   

Acquired Fund Fees and Expenses

     .66%        .66%        .66%        .66%        .66%        .66%        .66%   

Total Annual Fund Operating Expenses(1)

     .71%        .81%        .91%        1.01%        1.26%        1.16%        1.41%   

Expense Reimbursement

     (.12%     (.12%     (.12%     (.12%     (.12%     (.12%     (.12%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .59%        .69%        .79%        .89%        1.14%        1.04%        1.29%   


(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .59%, .69%, .79%, .89%, 1.14%, 1.04%, and 1.29% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 60      $ 211      $ 379      $ 867  

Class R5

   $ 70      $ 242      $ 434      $ 987  

Service Class

   $ 81      $ 274      $ 488      $ 1,105  

Administrative Class

   $ 91      $ 305      $ 542      $ 1,222  

Class A

   $ 685      $ 937      $ 1,212      $ 1,997  

Class R4

   $ 106      $ 352      $ 623      $ 1,395  

Class R3

   $ 131      $ 430      $ 756      $ 1,677  

Effective September 27, 2016, the following information replaces similar information found on page 76 for the MassMutual RetireSMARTSM 2030 Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.


Equity Funds

     76.2

MM Select Equity Asset (NTI)

     31.8

Select Overseas (J.P. Morgan/MFS/Harris)

     7.8

Fixed Income Funds

     20.7

Premier High Yield (Barings)

     5.4

Effective September 27, 2016, the following information replaces similar information found on page 83 for the MassMutual RetireSMARTSM 2035 Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
     Admini-
strative
Class
     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
    Admini-
strative
Class
    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .21%        .31%        .41%        .51%        .51%        .41%        .41%   

Acquired Fund Fees and Expenses

     .66%        .66%        .66%        .66%        .66%        .66%        .66%   

Total Annual Fund Operating Expenses(1)

     .87%        .97%        1.07%        1.17%        1.42%        1.32%        1.57%   

Expense Reimbursement

     (.26%     (.26%     (.26%     (.26%     (.26%     (.26%     (.26%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .61%        .71%        .81%        .91%        1.16%        1.06%        1.31%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .61%, .71%, .81%, .91%, 1.16%, 1.06%, and 1.31% for Classes I, R5, Service, Administrative, A, R4, and R3,


  respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 62      $ 242      $ 447      $ 1,040  

Class R5

   $ 73      $ 274      $ 502      $ 1,157  

Service Class

   $ 83      $ 305      $ 556      $ 1,274  

Administrative Class

   $ 93      $ 336      $ 609      $ 1,389  

Class A

   $ 686      $ 966      $ 1,275      $ 2,150  

Class R4

   $ 108      $ 383      $ 690      $ 1,559  

Class R3

   $ 133      $ 461      $ 822      $ 1,837  

Effective September 27, 2016, the following information replaces similar information found on page 84 for the MassMutual RetireSMARTSM 2035 Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     80.9

MM Select Equity Asset (NTI)

     32.9

Select Overseas (J.P. Morgan/MFS/Harris)

     8.4

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   


Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .08%        .18%        .28%        .38%        .38%        .28%        .28%   

Acquired Fund Fees and Expenses

     .67%        .67%        .67%        .67%        .67%        .67%        .67%   

Total Annual Fund Operating Expenses(1)

     .75%        .85%        .95%        1.05%        1.30%        1.20%        1.45%   

Expense Reimbursement

     (.15%     (.15%     (.15%     (.15%     (.15%     (.15%     (.15%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .60%        .70%        .80%        .90%        1.15%        1.05%        1.30%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .60%, .70%, .80%, .90%, 1.15%, 1.05%, and 1.30% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 61      $ 219      $ 397      $ 911  

Class R5

   $ 72      $ 251      $ 451      $ 1,030  

Service Class

   $ 82      $ 283      $ 506      $ 1,148  

Administrative Class

   $ 92      $ 314      $ 560      $ 1,264  

Class A

   $ 685      $ 945      $ 1,229      $ 2,036  

Class R4

   $ 107      $ 361      $ 640      $ 1,437  

Class R3

   $ 132      $ 439      $ 773      $ 1,718  


Effective September 27, 2016, the following information replaces similar information found on page 92 for the MassMutual RetireSMARTSM 2040 Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     82.7

MM Select Equity Asset (NTI)

     34.0

Select Overseas (J.P. Morgan/MFS/Harris)

     8.4

Effective September 27, 2016, the following information replaces similar information found on page 99 for the MassMutual RetireSMARTSM 2045 Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

     Class
I
    Class
R5
    Service
Class
   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

    .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

    None        None        None        None        .25%        .25%        .50%   

Other Expenses

    .37%        .47%        .57%        .67%        .67%        .57%        .57%   

Acquired Fund Fees and Expenses

    .67%        .67%        .67%        .67%        .67%        .67%        .67%   

Total Annual Fund Operating Expenses(1)

    1.04%        1.14%        1.24%        1.34%        1.59%        1.49%        1.74%   

Expense Reimbursement

    (.46%     (.46%     (.46%     (.46%     (.46%     (.46%     (.46%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

    .58%        .68%        .78%        .88%        1.13%        1.03%        1.28%   


(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .58%, .68%, .78%, .88%, 1.13%, 1.03% and 1.28% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 59      $ 269      $ 514      $ 1,215  

Class R5

   $ 69      $ 301      $ 568      $ 1,331  

Service Class

   $ 80      $ 332      $ 622      $ 1,445  

Administrative Class

   $ 90      $ 364      $ 675      $ 1,559  

Class A

   $ 684      $ 991      $ 1,336      $ 2,306  

Class R4

   $ 105      $ 410      $ 755      $ 1,727  

Class R3

   $ 130      $ 488      $ 886      $ 2,000  

Effective September 27, 2016, the following information replaces similar information found on page 100 for the MassMutual RetireSMARTSM 2045 Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     84.7

MM Select Equity Asset (NTI)

     34.4

Select Overseas (J.P. Morgan/MFS/Harris)

     8.6


Effective September 27, 2016, the following information replaces similar information found on page 107 for the MassMutual RetireSMARTSM 2050 Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

      Class
I
    Class
R5
    Service
Class
   

Admini-

strative
Class

    Class
A
    Class
R4
    Class
R3
 

Management Fees

     .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

     None        None        None        None        .25%        .25%        .50%   

Other Expenses

     .20%        .30%        .40%        .50%        .50%        .40%        .40%   

Acquired Fund Fees and Expenses

     .68%        .68%        .68%        .68%        .68%        .68%        .68%   

Total Annual Fund Operating Expenses(1)

     .88%        .98%        1.08%        1.18%        1.43%        1.33%        1.58%   

Expense Reimbursement

     (.29%     (.29%     (.29%     (.29%     (.29%     (.29%     (.29%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

     .59%        .69%        .79%        .89%        1.14%        1.04%        1.29%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .59%, .69%, .79%, .89%, 1.14%, 1.04%, and 1.29% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.


Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 60      $ 241      $ 449      $ 1,048  

Class R5

   $ 70      $ 273      $ 503      $ 1,165  

Service Class

   $ 81      $ 304      $ 557      $ 1,282  

Administrative Class

   $ 91      $ 336      $ 611      $ 1,397  

Class A

   $ 685      $ 965      $ 1,276      $ 2,157  

Class R4

   $ 106      $ 382      $ 691      $ 1,567  

Class R3

   $ 131      $ 460      $ 823      $ 1,845  

Effective September 27, 2016, the following information replaces similar information found on page 108 for the MassMutual RetireSMARTSM 2050 Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     90.5

MM Select Equity Asset (NTI)

     36.5

Select Overseas (J.P. Morgan/MFS/Harris)

     9.2

Effective September 27, 2016, the following information replaces similar information found on page 115 for the MassMutual RetireSMARTSM 2055 Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)

     None         None         None         None         None         None         None   


Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

     Class
I
    Class
R5
    Service
Class
    Admini-
strative
Class
    Class
A
    Class
R4
    Class
R3
 

Management Fees

    .00%        .00%        .00%        .00%        .00%        .00%        .00%   

Distribution and Service (Rule 12b-1) Fees

    None        None        None        None        .25%        .25%        .50%   

Other Expenses

    2.58%        2.68%        2.78%        2.88%        2.88%        2.78%        2.78%   

Acquired Fund Fees and Expenses

    .68%        .68%        .68%        .68%        .68%        .68%        .68%   

Total Annual Fund Operating Expenses(1)

    3.26%        3.36%        3.46%        3.56%        3.81%        3.71%        3.96%   

Expense Reimbursement

    (2.69%     (2.69%     (2.69%     (2.69%     (2.69%     (2.69%     (2.69%

Total Annual Fund Operating Expenses after Expense Reimbursement(2)

    .57%        .67%        .77%        .87%        1.12%        1.02%        1.27%   

 

(1) 

Because Total Annual Fund Operating Expenses include Acquired Fund Fees and Expenses, they may not correspond to the ratios of expenses to average daily net assets shown in the “Financial Highlights” tables in the Prospectus, which reflect the operating expenses of the Fund and do not include Acquired Fund Fees and Expenses.

 

(2) 

Effective September 27, 2016, MML Advisers changed the domestic and international mutual funds sponsored by MML Advisers or its affiliates (“Underlying Funds”) in which the Fund invests to include two recently-launched Underlying Funds. In connection with this change, MML Advisers entered into a written agreement, effective September 27, 2016, to cap the fees and expenses of the Fund (other than extraordinary litigation and legal expenses, interest expense, short sale dividend and loan expense, or other non-recurring or unusual expenses such as organizational expenses and shareholder meeting expenses), including Acquired Fund Fees and Expenses (calculated for this purpose at least monthly based on the Fund’s year to date average net assets of each Underlying Fund over the preceding period and the net expense ratio of each Underlying Fund stated in its then-current prospectus or most recent filing), through January 31, 2018, to the extent that such expenses would otherwise exceed .57%, .67%, .77%, .87%, 1.12%, 1.02%, and 1.27% for Classes I, R5, Service, Administrative, A, R4, and R3, respectively. The Total Annual Fund Operating Expenses after Expense Reimbursement shown in the above table may exceed these amounts, because, as noted in the previous sentence, certain fees and expenses are excluded from the cap. The agreement can only be terminated by mutual consent of the Board of Trustees on behalf of the Fund and MML Advisers. Because the expenses of the recently-launched Underlying Funds are lower than those of the Underlying Funds invested in by the Fund prior to September 27, 2016, MML Advisers expects that the cost to it of the Expense Reimbursement will be less than that shown in the table.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. It assumes that you invest $10,000 in each share class of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. For Class A shares, the example includes the initial sales charge. The example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses are exactly as described in the preceding table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

 

     1 Year      3 Years      5 Years      10 Years  

Class I

   $ 58      $ 660      $ 1,384      $ 3,306  

Class R5

   $ 68      $ 691      $ 1,433      $ 3,400  

Service Class

   $ 79      $ 721      $ 1,483      $ 3,493  

Administrative Class

   $ 89      $ 751      $ 1,532      $ 3,584  

Class A

   $ 683      $ 1,354      $ 2,133      $ 4,166  

Class R4

   $ 104      $ 796      $ 1,605      $ 3,721  

Class R3

   $ 129      $ 871      $ 1,726      $ 3,942  


Effective September 27, 2016, the following information replaces similar information found on page 116 for the MassMutual RetireSMARTSM 2055 Fund under the heading Principal Investment Strategies in the section titled Investments, Risks, and Performance:

The table below shows the Fund’s approximate allocation, as of September 27, 2016, among various asset classes and Underlying Funds in which the Fund invests 5% or more of its assets. Other Underlying Funds in which the Fund invests are listed under “Additional Information Regarding Investment Objectives and Principal Investment Strategies” in the Fund’s Prospectus. The Fund’s investment adviser, MML Advisers, intends to manage the Fund according to the Fund’s target asset allocation strategy, and does not intend to trade actively among Underlying Funds or to attempt to capture short-term market opportunities as primary activities. MML Advisers may modify the target asset allocation strategy or the selection of Underlying Funds from time to time, and may invest in other Underlying Funds, including any Underlying Funds that may be created in the future. At any given time, the Fund’s asset allocation may be affected by a variety of factors (such as, for example, whether an Underlying Fund is accepting additional investments). A description of the Underlying Funds is included in Appendix A of this Prospectus.

 

Equity Funds

     90.7

MM Select Equity Asset (NTI)

     35.2

Select Overseas (J.P. Morgan/MFS/Harris)

     9.3

Effective September 27, 2016, the following information replaces similar information found on page 123 for the MassMutual RetireSMARTSM 2060 Fund in the section titled Fees and Expenses of the Fund:

Shareholder Fees (fees paid directly from your investment)

 

      Class
I
     Class
R5
     Service
Class
    

Admini-

strative
Class

     Class
A
     Class
R4
     Class
R3
 

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

     None         None         None         None         5.75%         None         None   

Maximum Deferred Sales Charge (Load) (as a % of the lower of the original offering price or redemption proceeds)