Document and Entity Information - shares	9 Months Ended
	Jun. 30, 2024	Aug. 09, 2024
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2024
Document Transition Report	false
Entity File Number	000-56605
Entity Registrant Name	Gouverneur Bancorp, Inc.
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	37-2102925
Entity Address, Address Line One	42 Church Street
Entity Address, City or Town	Gouverneur
Entity Address State Or Province	NY
Entity Address, Postal Zip Code	13642
City Area Code	315
Local Phone Number	287-2600
Title of 12(b) Security	None
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		1,107,134
Entity Central Index Key	0001978811
Current Fiscal Year End Date	--09-30
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Amendment Flag	false