Mohammad Safdar, of Home Farm Close, was found to have broken the Housing Act 2004 due to having an unlicensed HMO at a property in Hexham Road, Reading.
A penalty notice was issued in July 2022 by Reading Borough Council, for a total of £22,861.
Safdar appealed against the fine, arguing that the property had been unlawfully sublet by his tenants, without his knowledge.
The appeal was dismissed after Reading Borough Council was able to call the former tenants of the property as witnesses, who all confirmed they had rented their rooms from Safdar, as well as paying him the rent directly.
Safda had previously been issued with a penalty notice for the same offence at a different address, where he also claimed the property had been unlawfully sublet by the tenants.
Reading Borough Council said the case served as a reminder that all properties occupied by more than one household, and where there were five or more occupants, require a licence from the council. If this does not happen, financial penalties of up to £30,000 can be issued, as an alternative to prosecution.