Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

BMO FUNDS, INC.

Prospectus Date

rr_ProspectusDate

Dec. 28, 2012

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Large-Cap Value Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Large-Cap Value Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Large-Cap Value Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Large-Cap Growth Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Large-Cap Growth Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Large-Cap Growth Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Mid-Cap Value Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Mid-Cap Value Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Mid-Cap Value Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Mid-Cap Growth Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Mid-Cap Growth Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Mid-Cap Growth Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Small-Cap Growth Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Small-Cap Growth Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Small-Cap Growth Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Government Income Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Government Income Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Government Income Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Short-Intermediate Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Short-Intermediate Bond Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Short-Intermediate Bond Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Intermediate Tax-Free Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Intermediate Tax-Free Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Intermediate Tax-Free Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Short-Term Income Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Short-Term Income Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Short-Term Income Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Aggregate Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Aggregate Bond Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Aggregate Bond Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO TCH Core Plus Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO TCH Core Plus Bond Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO TCH Core Plus Bond Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO TCH Corporate Income Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO TCH Corporate Income Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO TCH Corporate Income Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Small-Cap Value Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Small-Cap Value Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Small-Cap Value Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Dividend Income Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Dividend Income Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Dividend Income Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Monegy High Yield Bond Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Monegy High Yield Bond Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Monegy High Yield Bond Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Low Volatility Equity Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Low Volatility Equity Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Low Volatility Equity Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Short Tax-Free Fund

Risk/Return:

rr_RiskReturnAbstract

Supplement [Text Block]

mfibmo_SupplementTextBlock

BMO FUNDS, INC.

Prospectus Supplement

June 14, 2013

To Prospectus Dated December 29, 2012, as supplemented April 9, 2013 and May 10, 2013

BMO Funds is making certain updates to its Prospectus. Accordingly, the Funds’ Prospectus is revised as follows, effective immediately:

Elimination of Redemption Fee for Certain BMO Funds

The 2.00% redemption fee relating to redemptions or exchanges of shares held less than 30 days after the purchase of such shares is eliminated for the following Funds: BMO Low Volatility Equity Fund, BMO Large-Cap Value Fund, BMO Dividend Income Fund, BMO Large-Cap Growth Fund, BMO Mid-Cap Value Fund, BMO Mid-Cap Growth Fund, BMO Small-Cap Value Fund, BMO Small-Cap Growth Fund, BMO Short Tax-Free Fund, BMO Short-Term Income Fund, BMO Short-Intermediate Bond Fund, BMO Intermediate Tax-Free Fund, BMO Government Income Fund, BMO TCH Corporate Income Fund, BMO Aggregate Bond Fund, BMO TCH Core Plus Bond Fund, and BMO Monegy High Yield Bond Fund.

Accordingly, the line item for “Redemption Fee” in the table under “Fund Summary—Fees and Expenses of the Fund” in the Prospectus for each of the above-referenced Funds is hereby changed from “2.00%” to “None.”

BMO Short Tax-Free Fund | Class Y

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none

BMO Short Tax-Free Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Redemption Fee (as a percentage of amount redeemed, for shares held less than 30 days)

rr_RedemptionFeeOverRedemption

none