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Check or change your tax code

Your employer or pension provider uses your tax code to work out how much Income Tax to take from your pay. A wrong code means you pay too much or too little.

Applies to: Whole UK

Go to the official website: gov.uk

Official links

Official source	Applies to
GOV.UK: tax codes www.gov.uk/tax-codes	Whole UK
GOV.UK: check your Income Tax for the current year www.gov.uk/check-income-tax-current-year	Whole UK

Who handles it

HM Revenue & Customs (HMRC)

Collects taxes and National Insurance and pays Child Benefit. You deal with it for Income Tax, Self Assessment, PAYE and your tax code.

gov.uk View details »

Step by step

Find your tax code on your payslip, in the HMRC app, online or on a Tax Code Notice letter.
Use the GOV.UK tool to check what the numbers and letters mean. A code ending in W1, M1 or X is an emergency code.
If it looks wrong, sign in to the Check your Income Tax service and update your jobs, pensions, income, company benefits and expenses.
HMRC tells you and your employer the new code within 15 working days. It should show on your next or following payslip if you are paid monthly, or the third if weekly.

What you need

A recent payslip
Your P45 from your previous job, if you changed jobs
Photo ID such as a passport or driving licence, if you need to prove your identity online

Common mistakes

Staying on an emergency tax code for months without checking it.
Not asking your old employer for a P45 when you leave a job.
Calling HMRC straight after starting a new job: wait 35 days so they receive your new income details.