Income tax

Your coding notice

By Ian Robinson

Article 4 of 7

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Your coding notice

A coding notice is a document produced by HMRC showing how your tax code is calculated. 

Coding notices are normally sent in January or February each year so that any changes can be put into effect at the beginning of the next tax year in April. You may receive one at other times if the tax rules or your circumstances change. 

It's worth knowing that you may not get a coding notice at all; for example, if the letter in your code is L, P, V or Y, your employer may be able to alter your code automatically.

More than one tax code

You get a separate tax code for each job or pension. Your personal allowances will be given against what your tax office thinks is your main job, though you can ask to have this set against another source if you prefer. 

Your tax office may instruct whoever pays your second income to deduct tax at the basic rate (20%) or higher rate (40%), using the BR or DO code. 

If this results in you paying too much or too little tax over the year, HMRC changes your tax code to make sure you pay the correct amount.