Taxman says the tax I owe will be collected by restricting my PAYE code for 2012/13. What does this mean?

Q. The Tax Office has written to me saying £2,800 tax I owe will be collected by restricting my PAYE code for 2012/13. What does this mean?

A. The Taxman is now permitted to collect up to £3,000 of unpaid tax or overpaid tax credits through PAYE codes. Your PAYE code tells your employer how much of your income to treat as tax free, and thus how much tax to deduct from the rest. A common PAYE code for 2011/12 would be 747L, which gives you tax free income of £7,475 for the year. If you owe £2,800 in unpaid tax, and your highest marginal tax rate is 40%, your tax free income will be reduced by £7,000 (£2,800/ 40%), leaving you with tax free income of £475 and a PAYE code of 47L. The numbers will be slightly different in 2012/13, but essentially you will pay more tax each month from April 2012 until the tax debt is eliminated.