v3.26.1
Cover
Jul. 23, 2026
Cover [Abstract]  
Document Type 8-K
Amendment Flag false
Document Period End Date Jul. 23, 2026
Entity File Number 333-294289
Entity Registrant Name CSB Financial Inc.
Entity Central Index Key 0002114521
Entity Tax Identification Number 41-4994538
Entity Incorporation, State or Country Code MD
Entity Address, Address Line One 503 West Plane Street
Entity Address, City or Town Bethel
Entity Address, State or Province OH
Entity Address, Postal Zip Code 45106
City Area Code 513
Local Phone Number 734-4445
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company true
Elected Not To Use the Extended Transition Period false