v3.26.3
Form N-1A Cover
May 31, 2026
Prospectus [Line Items]  
Document Type 485BPOS
Amendment Flag false
Registrant Name AB MUNICIPAL INCOME FUND, INC.
Entity Central Index Key 0000798737
Entity Investment Company Type N-1A
Document Period End Date May 31, 2026
Prospectus Date Sep. 30, 2026