Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

CALVERT FUND

Prospectus Date

rr_ProspectusDate

Jan. 31, 2012

Supplement [Text Block]

cf4_SupplementTextBlock

SUPPLEMENT TO

CALVERT HIGH YIELD BOND FUND

Calvert Income Funds Prospectus
Class A, B, C, O and Y
dated January 31, 2012, as revised April 27, 2012

Date of supplement: November 1, 2012

Calvert investment Management, inc. (the “Advisor”) has contractually agreed to further waive fees or reimburse expenses for Class A, Class C and Class Y of the Fund, so that direct net operating expenses will not exceed 1.07%, 2.07% and 0.82%, respectively. The new expense limitation agreements are effective November 1, 2012, through January 31, 2014.

To reflect the new expense limitations, the table contained under “Fees and Expenses of the Fund” for Calvert High Yield Bond Fund on page 24 of the Prospectus is deleted and replaced with the following:

Shareholder Fees (fees paid directly from your investment)

	Class A	Class C	Class Y
Maximum sales charge (load) on	3.75%	None	None
purchases (as a % of offering price)
Maximum deferred sales charge	None	1.00%	None
(load) (as a % of amount purchased
or redeemed, whichever is lower) 1
Redemption fee (as a % of amount	2.00%	2.00%	2.00%
redeemed or exchanged within 30
days of purchase)

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

	Class A	Class C	Class Y
Management fees	0.75%	0.75%	0.75%
Distribution and service (12b-1) fees	0.25%	1.00%	None
Other expenses	0.56%	0.72%	2,723.09%
Total annual fund operating expenses	1.56%	2.47%	2,723.84%
Less fee waiver and/or expense	(0.49%)	(0.40%)	(2,723.02%)
reimbursement 2
Net expenses	1.07%	2.07%	0.82%

Footnote 2 to the table referenced above is deleted and replaced with the following:

² The investment advisor has agreed to contractually limit direct net annual fund operating expenses through January 31, 2014. Direct net operating expenses will not exceed 1.07% for Class A, 2.07% for Class C and 0.82% for Class Y. Only the Board of Trustees of the Fund may terminate the Fund’s expense cap before the contractual period expires.

The table contained under “Fees and Expenses of the Fund - Example” for Calvert High Yield Bond Fund on page 24 of the Prospectus is deleted and replaced with the following:

Share Class	1 Year	3 Years	5 Years	10 Years
Class A	$480	$803	$1,148	$2,122
Class C
Expenses assuming
redemption	$310	$731	$1,280	$2,776
Expenses assuming	$210	$731	$1,280	$2,776
no redemption
Class Y	$84	$721	$1,385	$3,163

Retail | Calvert High Yield Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

cf4_SupplementTextBlock

SUPPLEMENT TO

CALVERT HIGH YIELD BOND FUND

Calvert Income Funds Prospectus
Class A, B, C, O and Y
dated January 31, 2012, as revised April 27, 2012

Date of supplement: November 1, 2012

Calvert investment Management, inc. (the “Advisor”) has contractually agreed to further waive fees or reimburse expenses for Class A, Class C and Class Y of the Fund, so that direct net operating expenses will not exceed 1.07%, 2.07% and 0.82%, respectively. The new expense limitation agreements are effective November 1, 2012, through January 31, 2014.

To reflect the new expense limitations, the table contained under “Fees and Expenses of the Fund” for Calvert High Yield Bond Fund on page 24 of the Prospectus is deleted and replaced with the following:

Shareholder Fees (fees paid directly from your investment)

	Class A	Class C	Class Y
Maximum sales charge (load) on	3.75%	None	None
purchases (as a % of offering price)
Maximum deferred sales charge	None	1.00%	None
(load) (as a % of amount purchased
or redeemed, whichever is lower) 1
Redemption fee (as a % of amount	2.00%	2.00%	2.00%
redeemed or exchanged within 30
days of purchase)

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

	Class A	Class C	Class Y
Management fees	0.75%	0.75%	0.75%
Distribution and service (12b-1) fees	0.25%	1.00%	None
Other expenses	0.56%	0.72%	2,723.09%
Total annual fund operating expenses	1.56%	2.47%	2,723.84%
Less fee waiver and/or expense	(0.49%)	(0.40%)	(2,723.02%)
reimbursement 2
Net expenses	1.07%	2.07%	0.82%

Footnote 2 to the table referenced above is deleted and replaced with the following:

² The investment advisor has agreed to contractually limit direct net annual fund operating expenses through January 31, 2014. Direct net operating expenses will not exceed 1.07% for Class A, 2.07% for Class C and 0.82% for Class Y. Only the Board of Trustees of the Fund may terminate the Fund’s expense cap before the contractual period expires.

The table contained under “Fees and Expenses of the Fund - Example” for Calvert High Yield Bond Fund on page 24 of the Prospectus is deleted and replaced with the following:

Share Class	1 Year	3 Years	5 Years	10 Years
Class A	$480	$803	$1,148	$2,122
Class C
Expenses assuming
redemption	$310	$731	$1,280	$2,776
Expenses assuming	$210	$731	$1,280	$2,776
no redemption
Class Y	$84	$721	$1,385	$3,163

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

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

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

January 31, 2014

Retail | Calvert High Yield Bond Fund | Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

3.75%

Maximum deferred sales charge (load) (as a % of amount purchased or redeemed, whichever is lower)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Redemption fee (as a % of amount redeemed or exchanged within 30 days of purchase)

rr_RedemptionFeeOverRedemption

2.00%

Management fees

rr_ManagementFeesOverAssets

0.75%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other expenses

rr_OtherExpensesOverAssets

0.56%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.56%

Less fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.49%)

^[1]

Net expenses

rr_NetExpensesOverAssets

1.07%

1 Year

rr_ExpenseExampleYear01

480

3 Years

rr_ExpenseExampleYear03

803

5 Years

rr_ExpenseExampleYear05

1,148

10 Years

rr_ExpenseExampleYear10

2,122

Retail | Calvert High Yield Bond Fund | Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum deferred sales charge (load) (as a % of amount purchased or redeemed, whichever is lower)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Redemption fee (as a % of amount redeemed or exchanged within 30 days of purchase)

rr_RedemptionFeeOverRedemption

2.00%

Management fees

rr_ManagementFeesOverAssets

0.75%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.72%

Total annual fund operating expenses

rr_ExpensesOverAssets

2.47%

Less fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.40%)

^[1]

Net expenses

rr_NetExpensesOverAssets

2.07%

1 Year

rr_ExpenseExampleYear01

310

3 Years

rr_ExpenseExampleYear03

731

5 Years

rr_ExpenseExampleYear05

1,280

10 Years

rr_ExpenseExampleYear10

2,776

1 Year

rr_ExpenseExampleNoRedemptionYear01

210

3 Years

rr_ExpenseExampleNoRedemptionYear03

731

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,280

10 Years

rr_ExpenseExampleNoRedemptionYear10

2,776

Retail | Calvert High Yield Bond Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) on purchases (as a % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum deferred sales charge (load) (as a % of amount purchased or redeemed, whichever is lower)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Redemption fee (as a % of amount redeemed or exchanged within 30 days of purchase)

rr_RedemptionFeeOverRedemption

2.00%

Management fees

rr_ManagementFeesOverAssets

0.75%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

2723.09%

Total annual fund operating expenses

rr_ExpensesOverAssets

2723.84%

Less fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(2723.02%)

^[1]

Net expenses

rr_NetExpensesOverAssets

0.82%

1 Year

rr_ExpenseExampleYear01

84

3 Years

rr_ExpenseExampleYear03

721

5 Years

rr_ExpenseExampleYear05

1,385

10 Years

rr_ExpenseExampleYear10

3,163

[1] The investment advisor has agreed to contractually limit direct net annual fund operating expenses through January 31, 2014. Direct net operating expenses will not exceed 1.07% for Class A, 2.07% for Class C and 0.82% for Class Y. Only the Board of Trustees of the Fund may terminate the Fund's expense cap before the contractual period expires.