497

Adaptive Equity Fund

All Cap Growth Fund

Capital Value Fund

April 26, 2017

EXPLANATORY NOTE

On behalf of the Adaptive Equity Fund, All Cap Growth Fund and Capital Value Fund, each a series of American Century Mutual Funds, Inc. (the “Corporation”), and pursuant to Rule 497(e) under the Securities Act of 1933, as amended (the “Securities Act”), the purpose of this filing is to submit an interactive data file in the manner provided by Rule 405 of Regulation S-T and General Instruction C.3.(g) of Form N-1A. The interactive data file included as an exhibit to this filing relates to the prospectus supplement filed with the Securities and Exchange Commission on behalf of the Corporation pursuant to Rule 497(e) under the Securities Act on April 7, 2017; such filing (Accession Number 0000100334-17-000086) is incorporated by reference into this Rule 497 Document.

EXHIBIT INDEX

EXHIBIT NUMBER	DESCRIPTION OF DOCUMENT
Exhibit - 101.CAL	XBRL Taxonomy Extension Calculation Linkbase Document
Exhibit - 101.INS	XBRL Instance Document
Exhibit - 101.SCH	XBRL Taxonomy Extension Schema Document
Exhibit - 101.PRE	XBRL Taxonomy Extension Presentation Linkbase Document
Exhibit - 101.DEF	XBRL Taxonomy Extension Definition Linkbase Document
Exhibit - 101.LAB	XBRL Taxonomy Extension Label Linkbase Document

XML

Apr. 10, 2017

American Century Mutual Funds, Inc

Prospectus Supplement

Supplement dated April 10, 2017

California Long-Term Tax-Free Fund

(Prospectus dated January 1, 2017)

Adaptive Equity Fund n All Cap Growth Fund n Capital Value Fund

(Prospectuses dated March 1, 2017)

Global Allocation Fund

(Prospectus dated April 1, 2017)

Emerging Markets Small Cap Fund n Focused International Growth Fund n Global Small Cap Fund n International Opportunities Fund n International Value Fund

(Prospectuses dated April 1, 2017)

AC Alternatives Market Neutral Value Fund

(Prospectus dated August 1, 2016)

Core Equity Plus Fund n Emerging Markets Value Fund n Global Gold Fund n

International Core Equity Fund

(Prospectuses dated November 1, 2016)

All references to Institutional Class are changed to I Class. Effective with this change, I Class shares are available for purchase without sales charges or commissions by endowments, foundations, large institutional investors and financial intermediaries. Employer-sponsored retirement plans may not invest in I Class shares, except that plans invested in the I Class prior to April 10, 2017 may make additional purchases.

The following is added as the last sentence to the first paragraph under Fees and Expenses in the prospectuses.

Additional information about sales charge discounts can be found in Appendix A of the prospectus.

XML

Label

Element

Value

Prospectus:

rr_ProspectusTable

Document Type

dei_DocumentType

497

Document Period End Date

dei_DocumentPeriodEndDate

Apr. 07, 2017

Entity Registrant Name

dei_EntityRegistrantName

American Century Mutual Funds, Inc.

Central Index Key

dei_EntityCentralIndexKey

0000100334

Amendment Flag

dei_AmendmentFlag

false

Document Creation Date

dei_DocumentCreationDate

Apr. 07, 2017

Document Effective Date

dei_DocumentEffectiveDate

Mar. 01, 2017

Prospectus Date

rr_ProspectusDate

Mar. 01, 2017

American Century Mutual Funds, Inc

Prospectus:

rr_ProspectusTable

Supplement [Text Block]

ck0000100334_SupplementTextBlock

Prospectus Supplement

Supplement dated April 10, 2017

California Long-Term Tax-Free Fund

(Prospectus dated January 1, 2017)

Adaptive Equity Fund n All Cap Growth Fund n Capital Value Fund

(Prospectuses dated March 1, 2017)

Global Allocation Fund

(Prospectus dated April 1, 2017)

Emerging Markets Small Cap Fund n Focused International Growth Fund n Global Small Cap Fund n International Opportunities Fund n International Value Fund

(Prospectuses dated April 1, 2017)

AC Alternatives Market Neutral Value Fund

(Prospectus dated August 1, 2016)

Core Equity Plus Fund n Emerging Markets Value Fund n Global Gold Fund n

International Core Equity Fund

(Prospectuses dated November 1, 2016)

All references to Institutional Class are changed to I Class. Effective with this change, I Class shares are available for purchase without sales charges or commissions by endowments, foundations, large institutional investors and financial intermediaries. Employer-sponsored retirement plans may not invest in I Class shares, except that plans invested in the I Class prior to April 10, 2017 may make additional purchases.

The following is added as the last sentence to the first paragraph under Fees and Expenses in the prospectuses.

Additional information about sales charge discounts can be found in Appendix A of the prospectus.