Employers are encouraged to identify and pay back any over-payments as soon as possible. Under powers conferred on HMRC under the 2020 Finance Act, a penalty of up to 100% of the overpayment may be levied if the employer has not notified or repaid the amount over-claimed within 90 days of its receipt.
As an additional incentive to encourage compliance, the Government has published the names of employers claiming and the amount they have claimed.