v3.26.1
Cover
Mar. 30, 2026
Cover [Abstract]  
Document Type 8-K
Amendment Flag false
Document Period End Date Mar. 30, 2026
Entity File Number 333-290457
Entity Registrant Name PSB Financial, Inc.
Entity Central Index Key 0002087419
Entity Tax Identification Number 39-4296886
Entity Incorporation, State or Country Code MD
Entity Address, Address Line One 202 North Main Street
Entity Address, Address Line Two P.O. Box 191
Entity Address, City or Town Deer Lodge
Entity Address, State or Province MT
Entity Address, Postal Zip Code 59722
City Area Code (406)
Local Phone Number 846-2202
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