Are you one of the lucky 4.3 million taxpayers whom HMRC say are due a tax rebate due to their blunders in operating the PAYE system?

Or are you one of the 1.4 million whom HMRC say owe an average of £1,428? 'It's not my fault' I hear you shout but what can be done?

Here are answers to some of the questions you may have.

I don't pay higher rate tax or do a tax return and all my tax is deducting by my employer, so how can I owe HMRC tax?

The amount of tax deducted on your payslip is determined by your tax code. If you have a high tax code you will pay less tax and vice versa. But if HMRC have given you a tax code that is higher than it should be, you will pay less tax on your payslip than you should and would, unknowingly, owe tax to HMRC.

How will I know if I owe anything?

HMRC will be writing to everyone. They are currently sending £45,000 letters a week which could take until the end of next year to send all the letters. HMRC say it will be completed by Christmas.

It's their fault - can't they write it off?

With £2 billion owed HMRC cannot really afford to write it off. They also have a statutory duty to collect all tax owed so would find it difficult to write it off. They have mooted the possibility that sums under £300 will not be collected, possibly on the grounds that the cost of collecting it would outweigh the tax collected.

I can't afford to pay it back, so what can HMRC do?

HMRC have a few ways of dealing with this. They can reduce your tax code so that you pay more tax on each payslip. HMRC have talked about allowing sums of under £2,000 to be repaid by the end of the 2011/12 tax year. For sums over £2,000 they normally require immediate settlement but may be prepared to accept payment over 3 years.

Is there a loophole I can use to get away without paying?

Extra-statutory Concession A19 states that if you have given HMRC all the information they need to get your tax right, HMRC then have 12 months in which to make any corrections. If they exceed the 12 months you can make a claim for the tax to be waived. However, a spokesman for HMRC said that they would be resisting such claims.

HMRC have recently sent me an email telling me I have a tax rebate and I should follow a link. Is this the best way to claim the rebate?

This will be a scam email. HMRC never, ever use email to correspond with taxpayers. Make sure you delete it from your inbox. This tax code farce will see the fraudsters target people to get their details for identity fraud including selling them on to criminal gangs.

HMRC say that it is improvements to the system that have allowed these errors to come to lightand that the system was created when tax affairs were much simpler. It is more close to the truth to say that the whole tax system is too complex to be corrected by some tax code changes. Let's hope that the Office of Tax Simplification, newly formed by the coalition government, can live up to its name.