Document And Entity Information - shares
 3 Months Ended
Mar. 31, 2018
Apr. 30, 2018
Document Information [Line Items]    
Entity Registrant Name Bancorp 34, Inc.  
Entity Central Index Key 0001668340  
Trading Symbol bctf  
Current Fiscal Year End Date --12-31  
Entity Filer Category Smaller Reporting Company  
Entity Current Reporting Status Yes  
Entity Voluntary Filers No  
Entity Well-known Seasoned Issuer No  
Entity Common Stock, Shares Outstanding (in shares)   3,404,065
Document Type 10-Q  
Document Period End Date Mar. 31, 2018  
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q1  
Amendment Flag false