What is the difference between a P45 and a P46?

You get a P45 when you leave employment and you complete a P46 when you start employment should you not have a P45 from a recent previous employer.

Your P45 will show various pieces of information including your PAYE reference code and how much you earned and paid in tax during the tax year. Your P45 will be in 3 parts. When you find another job you should give parts 2 and 3 to your new employer. This will allow them to see how much tax you have paid and put you on the correct tax code. Often people lose their P45 or forget to give it to their employer. When this happens the employer is forced to put you on an emergency tax code which often means that you end up overpaying tax until you claim a tax refund at the end of the tax year.

If you do not want to show your employer your P45 because you want to keep your previous wage confidential then you can get around giving them your P45 by sending parts 2 and 3 to your tax office telling them where you are working. You should make sure that you do this as soon as possible otherwise you could be put on the wrong tax code.

If you lose your P45 or were not given one by your employer, because they say, went bankrupt. You can give your new employer a P46 instead. You need to complete the P46, and once you have, give it to your new employer so that they can put you on the right tax code.