Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Aug. 31, 2019
Registrant Name	BNY MELLON MUNICIPAL FUNDS, INC.
Entity Central Index Key	0000878092
Entity Inv Company Type	N-1A
Amendment Flag	false
Document Creation Date	Dec. 20, 2019
Document Effective Date	Dec. 31, 2019
Prospectus Date	Dec. 31, 2019
BNY Mellon AMT-Free Municipal Bond Fund \| Class Y
Prospectus:
Trading Symbol	DMUYX
BNY Mellon AMT-Free Municipal Bond Fund \| Class I Shares
Prospectus:
Trading Symbol	DMBIX
BNY Mellon AMT-Free Municipal Bond Fund \| Class Z
Prospectus:
Trading Symbol	DRMBX
BNY Mellon AMT-Free Municipal Bond Fund \| Class C
Prospectus:
Trading Symbol	DMUCX
BNY Mellon AMT-Free Municipal Bond Fund \| Class A
Prospectus:
Trading Symbol	DMUAX
BNY Mellon High Yield Municipal Bond Fund \| Class Y
Prospectus:
Trading Symbol	DHYYX
BNY Mellon High Yield Municipal Bond Fund \| Class I Shares
Prospectus:
Trading Symbol	DYBIX
BNY Mellon High Yield Municipal Bond Fund \| Class C
Prospectus:
Trading Symbol	DHYCX
BNY Mellon High Yield Municipal Bond Fund \| Class A
Prospectus:
Trading Symbol	DHYAX
BNY Mellon High Yield Municipal Bond Fund \| Class Z
Prospectus:
Trading Symbol	DHMBX

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