v3.26.3
Form N-1A Cover
Jun. 30, 2025
Prospectus [Line Items]  
Document Type 497
Amendment Flag false
Registrant Name BLACKROCK MULTI STATE MUNICIPAL SERIES TRUST
Entity Central Index Key 0000774013
Entity Investment Company Type N-1A
Document Period End Date Jun. 30, 2025
Prospectus Date Oct. 28, 2025