Document and Entity Information	Total
Prospectus:
Document Type	497
Document Period End Date	Aug. 31, 2021
Entity Registrant Name	BNY MELLON MUNICIPAL FUNDS, INC.
Entity Central Index Key	0000878092
Entity Inv Company Type	N-1A
Amendment Flag	false
Document Creation Date	Jul. 11, 2022
Document Effective Date	Jul. 11, 2022
Prospectus Date	Dec. 31, 2021
BNY Mellon AMT-Free Municipal Bond Fund \| Class A
Prospectus:
Trading Symbol	DMUAX
BNY Mellon AMT-Free Municipal Bond Fund \| Class C
Prospectus:
Trading Symbol	DMUCX
BNY Mellon AMT-Free Municipal Bond Fund \| Class Z
Prospectus:
Trading Symbol	DRMBX
BNY Mellon AMT-Free Municipal Bond Fund \| Class I Shares
Prospectus:
Trading Symbol	DMBIX
BNY Mellon AMT-Free Municipal Bond Fund \| Class Y
Prospectus:
Trading Symbol	DMUYX

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