HMRC has been accused of 'gross incompetence' having incorrectly fined a Norfolk business for late tax returns – despite the deadline being in a fortnight.

Debit and Credit Accountancy, a family run business based in Wroxham, spotted the taxman's blunder when a client was slapped with the £100 fine.

The penalty notice related to late tax returns - which Debit and Credit are paid to organise on behalf of their customers - for the year ending April 2019.

However the deadline for these returns to be made online is in more than two weeks on January 31.

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Deborah Williams, co-founder of Debit and Credit, said the error has caused them reputational damage and added distress at an already notoriously busy time.

"We work seven days a week in January to get our clients' returns in on time," she said. "We have more than 500 clients and we have about 80 companies left to file for. We believe it's an automatically generated message because the reminders usually are - so my worry is that although only one of our clients has received this fine so far, there is the potential for all the others to get it as well.

"We're paid to file these tax returns for them so to the client it looks bad on our part," she said. "It's already a very stressful time and this has made it so much worse. Our client obviously wasn't happy, so it was very unwelcome."

Following investigations HMRC quashed the fine.

Miss Williams founded Debit and Credit with husband - and former tax inspector - Greg Eade in 2005.

"We've never had a problem like this before," she said. "It's ironic because my husband actually used to be a tax inspector. We've had more minor issues with HMRC but this is imply grossly incompetent - there are no other words for it.

"When I called HMRC the woman on the end of the phone was flabbergasted. I'd like an apology but I know I won't get one."

For more information about tax returns, and when your businesses' are due, visit the HMRC website at www.gov.uk/self-assessment-tax-returns.

HMRC was contacted for comment.