How do I check if I owe tax to HMRC?
Answered 17 March 2026
Based on the available sources, here is what I can tell you about checking whether you owe tax to HMRC:
HMRC Guidance / Practice
The clearest and most practical step identified in the sources is to use your Personal Tax Account:
"The easiest way to check or query this adjustment is by using your Personal Tax Account, go to gov.uk/personal-tax-account where you can view or change your information and contact us if you need additional support or if it will cause financial difficulty."
Other ways a tax liability may come to your attention include:
- Your tax code / P2 notice: If HMRC believes you owe tax, they may adjust your tax code and notify you via an Annual Coding Notice (P2), which will show any amount to be collected.
- Self Assessment tax return: If you are in Self Assessment, your tax return calculation will show any balancing payment owed. Your authorised agent can also "view your calculations and amounts owed and paid" on your behalf.
- HMRC compliance check: If HMRC conducts a compliance check and finds an underpayment, they will notify you directly.
⚠️ Important note: The retrieved sources do not contain a dedicated step-by-step guide specifically on how individuals check their tax position. For comprehensive guidance, you should visit gov.uk/personal-tax-account directly or contact HMRC. Be cautious of third-party "tax rebate" companies — a tribunal case in the sources illustrates how such companies can mislead taxpayers about their tax position.
Citation sources
Automatic note on P2 - Estimated tax you owe (this year) Due to an in year adjustment to your tax code(s) we think that you will owe HMRC £<IYA>. We are unable to collect the amount in full this year based on your current income. We have therefore included an adjustment to reduce your tax-free allowance by £<IYAR> so we can collect £<IYA> in equal instalments from now on by increasing the tax deducted from your wage, salary or pension so that the £<IYA> is paid by 5 April <YYYY>. We will confirm
ur UTR from HMRC. This should arrive in the post over the next few weeks so once you receive it could you please forward it to ourselves.” Email CACL to Appellant on 29 September 2016 following receipt of the UTR: “…we have now requested an agent authorisation code to let us act on your behalf. This will arrive in the post in the next week or so. Once you receive if you could forward it on and we will see what we can do for you.” Email Appellant to CACL on 14 October 2016 with authorisation code
h as you can off the arrears still owing. We will look at your class 2 NICs arrears later this year and decide if we will be able to have this collected through your tax code and if the arrears are passed to a DCA. 7. Will coding out impact any claims to benefit? If we collect the class 2 NICs you owe through your tax code then it will not be available to be used in benefit calculations until after the end of the tax in which it is collected. This will be after the deductions have been checked a
If the check shows there’s nothing wrong, we’ll end it as quickly as possible. If you’ve overpaid tax, we’ll repay this to you along with any interest due. If you’ve underpaid tax, you’ll need to repay this. We’ll charge you interest and may also charge you a penalty. We may issue a tax assessment or amend your tax return to collect any unpaid tax. If you owe us tax and cannot afford to pay it immediately, you can contact us about payment arrangements.
When authorised, your agent can: submit tax returns on your behalf make claims for tax relief in your tax returns discuss your current and previous tax returns with us view and change your details, such as sources of income provide bank details to us when repayment is due view and submit your updates (income and expenses) finalise your overall tax position view your calculations and amounts owed and paid cancel your Self Assessment registration Your agent can also access your Self Assessment det
Automatic note on P2 - Estimated tax you owe (this year) Due to an in year adjustment to your tax code(s) we think that you will owe HMRC £<IYA_CY+1>. We are unable to collect the amount this year based on your current income. We will confirm the exact amount you owe and collect any tax when we look at your tax return for the year. The easiest way to check or query this adjustment is by using your Personal Tax Account, go to gov.uk/personal-tax-account where you can view or change your informati