Document and Entity Information - $ / shares		9 Months Ended
May 09, 2018	Mar. 31, 2018
Details
Registrant Name		Southern Missouri Bancorp, Inc.
Registrant CIK		0000916907
SEC Form		10-Q
Period End date		Mar. 31, 2018
Fiscal Year End		--06-30
Trading Symbol		SMBC
Tax Identification Number (TIN)		431665523
Number of common stock shares outstanding	8,992,584
Filer Category		Accelerated Filer
Current with reporting		Yes
Voluntary filer		No
Well-known Seasoned Issuer		No
Amendment Flag		false
Document Fiscal Year Focus		2018
Document Fiscal Period Focus		Q3
Entity Incorporation, State Country Name		Missouri
Entity Address, Address Line One		2991 Oak Grove Road
Entity Address, City or Town		Poplar Bluff
Entity Address, State or Province		MO
Entity Address, Postal Zip Code		63901
City Area Code		573
Local Phone Number		778-1800
Entity Listing, Par Value Per Share	$ 0.01

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