Catherine McKinlay was caught following a routine check by the Department for Work and Pensions.
Officials discovered she had been claiming Incapacity Benefit for eight years while holding down a job as a cleaner.
McKinlay, 56, of Livingston, West Lothian, was working for Capital Cleaning Services in Edinburgh while pretending to be unfit.
She appeared for sentence at Livingston Sheriff Court yesterday after earlier pleading guilty to benefit fraud.
She was jailed for 95 days after a sheriff told her she couldn’t repay the money fast enough.