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Loans - Summary of loans (Details) - USD ($) | Sep. 30, 2025 | Jun. 30, 2025
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Loans and Leases Receivable Disclosure [Line Items] |  |
Interest receivable | $ 700,642 | $ 667,686
Total loans | 208,044,000 | 202,571,000
Deferred loan fees | (116,000) | (67,000)
Allowance for loan losses | (1,668,782) | (1,708,269)
Loans, net | 206,259,000 | 200,796,000
Provision for loans |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Interest receivable | 649,927 | 603,309
Commercial real estate | Commercial real estate |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | 91,406,000 | 91,867,000
Commercial | Commercial and industrial |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | 4,015,000 | 3,876,000
Commercial | Construction |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | 990,000 | 733,000
Commercial | Consumer |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | 2,009,000 | 1,957,000
Residential | One-to-four-family residential |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | 58,907,000 | 56,330,000
Residential | Multi-family real estate |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | $ 50,717,000 | $ 47,808,000

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