Check My Tax Code Online

Screenshot of the HMRC websites tax code checker tool

To check your tax code online, log in to your personal tax account on the HMRC website or use a government-approved tax app. Your tax code determines how much income tax is deducted from your paycheck.

How It Works

Your tax code is a combination of numbers and letters that tells your employer or pension provider how much tax to deduct from your wages or pension. The numbers represent your tax-free personal allowance, while the letters indicate specific circumstances affecting your tax, such as having a second job or receiving benefits.

Main Types of Tax Codes

Tax codes can vary based on your personal circumstances. Common types include:

Standard tax code: Typically 1257L for the 2023-24 tax year, meaning you get a £12,570 personal allowance.
Emergency tax code: Often BR or 0T, applied when HMRC doesn't have enough information about you.
K codes: Used when you have income that doesn't qualify for tax-free allowances, like company benefits.
NT codes: Indicate that no tax should be deducted, usually for low-income earners.

Why Check Your Tax Code

Checking your tax code ensures you're on the correct tax code and not overpaying or underpaying tax. Errors can happen due to changes in your personal circumstances, such as starting a new job, claiming benefits, or changes to your tax-free personal allowance. According to HMRC, around 3 million people are on the wrong tax code each year.

Common Misconceptions

Many people confuse their tax code with their National Insurance number or their Unique Taxpayer Reference (UTR). While these are also important identifiers in the UK tax system, they serve different purposes. Your National Insurance number tracks your contributions to the state pension and other benefits, while your UTR is used for self-assessment tax returns.

How to Correct an Incorrect Tax Code

If you discover an error in your tax code, contact HMRC immediately. You can do this online through your personal tax account, by phone, or by post. Provide details of the discrepancy and any supporting documents, such as P45 or P60 forms. HMRC will review your case and issue a corrected tax code if necessary.

For example, if you recently started a new job and received an emergency tax code, providing your P45 from your previous employer can help HMRC issue the correct tax code. This process usually takes a few weeks, but it's worth the wait to avoid overpaying or underpaying tax.

Checking your tax code online is a quick and easy way to ensure you're paying the right amount of tax. Regularly reviewing your tax code can prevent financial surprises and keep your tax affairs in order.