September 16, 2026

Starting a new job? That’s great, but do you know you might spot an unfamiliar tax code on your first payslip? Yes, you may be on an emergency tax code if your tax code ends in W1, M1, or X. This basically happens when HM Revenue and Customs (HMRC) does not yet have enough information about your income or previous employment. However, know that being placed on an emergency code does not necessarily mean you have done anything wrong. Let’s understand what an emergency code is, why it happens, how to check your tax code, and whether you pay too much or too little income tax. What is an Emergency Tax Code? An emergency tax code is a temporary PAYE tax code. This code is used when HMRC does not have enough information to calculate your normal tax code accurately. So, if you are starting a new job and your previous pay and tax details are not available, you may get an emergency code. Additionally, emergency codes can be used in some circumstances when you start receiving State Pension or certain company benefits. It can take up to 35 days from the date you start your job to update your tax code after receiving the necessary information. How do Emergency Tax Codes Work? Currently, HMRC identifies emergency codes by the suffixes W1, M1, or X. You may also see NONCUM on your payslip, depending on your employer’s payroll software. You might see an emergency tax code that normally ends in W1, M1, or X. For instance, 1257L W1, 1257L M1, and 1257L X. For the 2026/27 tax year, the standard emergency code is 1257L. The 1257L part reflects the standard £12,570 Personal Allowance. You may also see tax codes such as BR or 0T in Pay As You Earn (PAYE). However, these are not emergency tax codes. BR means all income from that job or pension is taxed at the basic rate. Whereas 0T means no Personal Allowance is available for that source. What do W1, M1 and X Mean? An individual is on an emergency tax code if their tax code ends in. W1 is used when you are paid weekly. M1 is used when you are paid monthly. X is used when your pay dates vary. Moreover, a NONCUM may appear on your payslip depending on your employer’s payroll software. How Do I Know if I’m on an Emergency Tax Code? You can check whether you are on an emergency code in several ways, such as: Your Payslip Check the tax code on your payslip. An emergency tax code usually ends in W1, M1, X, or NONCUM. For example, 1257L W1 or 1257L M1 specifies that the code is being operated on a non-cumulative basis. The HMRC App You can also use the HMRC app to view your tax code. Compare the code shown by HMRC with the code on your payslip to check whether they match. Your HMRC Personal Tax Account Sign in to your Personal Tax Account through the official government website. Check the tax code HMRC currently has for you and the employment or pension it relates to. Your P45 If you have recently changed jobs, check the tax code on your P45. Then compare it with the code on your new payslip. A different code does not automatically mean you are on an emergency tax code, because HMRC may have issued your employer with an updated code. If your new payslip has a code ending in W1, M1, X, or NONCUM, this indicates that the code is being operated on an emergency basis. Why Might HMRC Assign an Employee to an Emergency Tax Code? HMRC may assign an employee an emergency code when HMRC or the employer does not have enough information to calculate the correct PAYE tax code. This usually happens when an employee starts a new job, and their previous employment or tax details are not yet available. Remember, being on an emergency tax code does not necessarily mean you will overpay tax. You could pay too much or too little tax while the temporary code is being used, depending on your circumstances. Emergency codes can be used when you: Start a new job Without Providing a P45 Your new employer may put you on an emergency code if they don’t have details of your previous employment and tax record. Giving the right starter information helps your employer work out how to set up your PAYE record. Start a new PAYE job After Being Self-Employed Moving from self-employment to employment does not automatically result in an emergency tax code. However, you may be placed on one if HMRC or your new employer does not yet have enough information to establish the correct PAYE code. Start Receiving Taxable Pension Income or the State Pension Your State Pension and certain pension income can affect your tax position. HMRC may adjust your PAYE tax code so that the appropriate amount of tax is collected. Have Taxable Company Benefits Your tax code can be affected by benefits such as a company car or private medical insurance. HMRC could change your code when it gets information about your benefits. However, having a taxable benefit does not mean you will automatically be put on an emergency tax code. Have More than one Employment If you have more than one job, HMRC might give you different tax codes for your different sources of PAYE income. While having more than one job doesn’t automatically put you on an emergency tax code, changing jobs can sometimes result in a temporary code being issued. If HMRC later receives or obtains the information it needs to work out your tax position, it may issue an updated tax code to your employer. Your employer then implements the new code through PAYE. If you have overpaid tax, then you may be refunded depending on your circumstances, either through the revised code or a subsequent HMRC calculation. If you’re unsure why your tax code has