Label

Element

Value

Risk/Return:

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Registrant Name

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FIDELITY ABERDEEN STREET TRUST

Prospectus Date

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May 30, 2013

Fidelity Freedom K 2000 Fund

Risk/Return:

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Supplement [Text Block]

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Supplement to the
Fidelity Freedom K^® Funds
May 30, 2013
Prospectus

Strategic Advisers may modify the target asset allocation strategy for the Fidelity Freedom K Funds and modify the selection of underlying Fidelity funds for any Fidelity Freedom K Fund from time to time. Fidelity^® Series 1000 Value Index Fund, Fidelity^® Series Blue Chip Growth Fund, Fidelity Series Growth Company Fund, and Fidelity Series Small Cap Discovery Fund have been added to the selection of underlying funds. Each Fidelity Freedom K Fund is expected to cease its investments in Fidelity Blue Chip Growth Fund, Fidelity Growth Company Fund, Fidelity Series Large Cap Value Fund, Fidelity Small Cap Growth Fund, and Fidelity Small Cap Value Fund over time. Effective August 1, 2013, Fidelity Series Mega Cap Fund revised its investment objective to seek a high total return through a combination of current income and capital appreciation and eliminated its current policy to invest at least 80% of its assets in common stocks of companies with mega market capitalizations. In addition to other related policy changes, the fund also changed its name to "Fidelity Series Growth & Income Fund." Effective on or about January 1, 2014, a new target asset allocation strategy for the Fidelity Freedom K Funds will take effect. On or about September 26, 2013, Strategic Advisers began transitioning fund assets to achieve the desired target allocations. The modified asset allocation strategy is expected to result in changes to acquired fund fees and expenses reflected in each fund's fee table, which have been updated accordingly in the fee tables below. Commensurate with this change, on or about January 1, 2014, after the modified asset allocation strategy has been fully implemented, Strategic Advisers will replace the MSCI EAFE Index with the MSCI ACWI ex US Index as a component of each fund's composite benchmark.

The following information replaces similar information for Fidelity Freedom K Income Fund found in the "Fund Summary" section beginning on page 3 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.40%
Total annual fund operating expensesB	0.45%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 46
3 years	$ 144
5 years	$ 252
10 years	$ 567

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to a stable target asset allocation of approximately:

Domestic Equity Funds	17%
International Equity Funds	7%
Bond Funds	46%
Short-Term Funds	30%

The following information replaces similar information for Fidelity Freedom K 2000 Fund found in the "Fund Summary" section beginning on page 6 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.40%
Total annual fund operating expensesB	0.45%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 46
3 years	$ 144
5 years	$ 252
10 years	$ 567

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2000).

The following information replaces similar information for Fidelity Freedom K 2005 Fund found in the "Fund Summary" section beginning on page 9 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.45%
Total annual fund operating expensesB	0.50%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 51
3 years	$ 160
5 years	$ 280
10 years	$ 628

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2005).

The following information replaces similar information for Fidelity Freedom K 2010 Fund found in the "Fund Summary" section beginning on page 12 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.49%
Total annual fund operating expensesB	0.54%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 55
3 years	$ 173
5 years	$ 302
10 years	$ 677

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2010).

The following information replaces similar information for Fidelity Freedom K 2015 Fund found in the "Fund Summary" section beginning on page 16 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.52%
Total annual fund operating expensesB	0.57%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 58
3 years	$ 183
5 years	$ 318
10 years	$ 714

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2015).

The following information replaces similar information for Fidelity Freedom K 2020 Fund found in the "Fund Summary" section beginning on page 20 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.54%
Total annual fund operating expensesB	0.59%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 60
3 years	$ 189
5 years	$ 329
10 years	$ 738

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2020).

The following information replaces similar information for Fidelity Freedom K 2025 Fund found in the "Fund Summary" section beginning on page 23 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.57%
Total annual fund operating expensesB	0.62%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 63
3 years	$ 199
5 years	$ 346
10 years	$ 774

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2025).

The following information replaces similar information for Fidelity Freedom K 2030 Fund found in the "Fund Summary" section beginning on page 26 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.62%
Total annual fund operating expensesB	0.67%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 68
3 years	$ 214
5 years	$ 373
10 years	$ 835

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2030).

The following information replaces similar information for Fidelity Freedom K 2035 Fund found in the "Fund Summary" section beginning on page 29 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.63%
Total annual fund operating expensesB	0.68%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 69
3 years	$ 218
5 years	$ 379
10 years	$ 847

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2035).

The following information replaces similar information for Fidelity Freedom K 2040 Fund found in the "Fund Summary" section beginning on page 33 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.63%
Total annual fund operating expensesB	0.68%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 69
3 years	$ 218
5 years	$ 379
10 years	$ 847

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2040).

The following information replaces similar information for Fidelity Freedom K 2045 Fund found in the "Fund Summary" section beginning on page 36 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.64%
Total annual fund operating expensesB	0.69%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 70
3 years	$ 221
5 years	$ 384
10 years	$ 859

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2045).

The following information replaces similar information for Fidelity Freedom K 2050 Fund found in the "Fund Summary" section beginning on page 39 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.64%
Total annual fund operating expensesB	0.69%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 70
3 years	$ 221
5 years	$ 384
10 years	$ 859

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2050).

The following information replaces similar information for Fidelity Freedom K 2055 Fund found in the "Fund Summary" section beginning on page 42 under each of the headings indicated below.

Fee Table

Annual fund operating expenses
(expenses that you pay each year as a % of the value of your investment)

Management fee	None
Distribution and/or Service (12b-1) fees	None
Other expenses	0.05%
Acquired fund fees and expensesA	0.64%
Total annual fund operating expensesB	0.69%

^A Adjusted to reflect current fees.

^B Differs from the ratios of expenses to average net assets in the Financial Highlights section of the prospectus because of acquired fund fees and expenses.

1 year	$ 70
3 years	$ 221
5 years	$ 384
10 years	$ 859

Principal Investment Strategies

• Allocating assets among underlying Fidelity funds according to an asset allocation strategy that becomes increasingly conservative until it reaches approximately 17% in domestic equity funds, 7% in international equity funds, 46% in bond funds, and 30% in short-term funds (approximately 10 to 17 years after the year 2055).