The 1122L tax code means your employer or pension provider will treat £11,220 of your income as tax-free this year, which is £1,350 below the standard personal allowance of £12,570. HMRC reduces the allowance like this when you have taxable workplace benefits, an underpayment from an earlier year being clawed back, other untaxed income, or an adjusted net income high enough to taper the allowance. If the reduction doesn’t match your actual situation, you’re either overpaying or underpaying tax on every payslip until it’s corrected.
How the Number and Letter Work
Every PAYE code is a number plus a letter. Multiply the number by ten and you have your tax-free amount for the year: 1122 becomes £11,220. The letter L means you get the standard personal allowance with no unusual adjustments to your personal circumstances.1GOV.UK. Tax Codes: What Your Tax Code Means
The most common code right now is 1257L, giving the full £12,570 allowance. If yours is 1122L, HMRC has trimmed £1,350 off that figure for a specific reason.2GOV.UK. Income Tax Rates and Personal Allowances Anything you earn above £11,220 in the year gets taxed at the normal rates through PAYE. A wrong number in your code compounds every payday, so it’s worth understanding where the £1,350 came from.
Why £1,350 Has Been Deducted
HMRC doesn’t cut your allowance arbitrarily. The reduction reflects something the tax office knows or estimates about your income. Four causes turn up most often.
Taxable Workplace Benefits
Perks like private medical insurance, a company car, or fuel for personal use have a taxable value. Rather than billing you separately, HMRC collects the tax by shrinking your personal allowance. A company car with a taxable value of £1,350 would produce exactly the 1122L code. Your employer reports the benefit to HMRC on a P11D, and the adjustment feeds into your code for the following year.3GOV.UK. Expenses and Benefits for Employers
Underpaid Tax From a Previous Year
If you didn’t pay enough tax last year, HMRC often spreads the recovery across the current year by lowering your allowance instead of demanding a lump sum. A £1,350 shortfall drops your code from 1257L to 1122L, and the extra tax comes out gradually. You’ll usually get a P800 tax calculation first showing how the underpayment was worked out.4GOV.UK. Tax Overpayments and Underpayments
Untaxed Income From Other Sources
Income that isn’t taxed at source can also trigger a code reduction: rental income below the self-assessment threshold, untaxed savings interest, or small amounts of freelance work. HMRC estimates the tax due and builds it into your PAYE code so your main employer collects it automatically. The £1,350 may be a single item or several smaller adjustments added together.
High-Income Allowance Tapering
If your adjusted net income exceeds £100,000, your personal allowance drops by £1 for every £2 above that threshold, and disappears completely at £125,140.2GOV.UK. Income Tax Rates and Personal Allowances Income of £102,700 reduces the £12,570 allowance by £1,350 (half of £2,700), landing on 1122L. Salary sacrifice into a pension can bring adjusted net income back below £100,000 and restore the allowance, which is why this threshold gets so much attention when income fluctuates around it.
The W1, M1 and NONCUM Versions
If your code appears as 1122L W1, 1122L M1, or 1122L NONCUM, you’re on an emergency basis. This usually happens after starting a new job when your employer doesn’t yet have a P45 or the correct instructions from HMRC.5GOV.UK. Understanding Your Employees’ Tax Codes: What the Letters Mean
Under emergency coding, tax is worked out on each pay period in isolation, ignoring what you’ve earned earlier in the year. That often means overpaying in the short term. Once HMRC issues the proper cumulative code, the next payslip should catch up. If the emergency marker sticks around for more than a couple of months, ring HMRC rather than wait.
Checking Whether 1122L Is Right for You
The document that shows how HMRC arrived at your code is your coding notice, often called a P2. It lists the £12,570 starting point, every deduction, and the resulting code. If a paper copy hasn’t arrived, the same breakdown is in your personal tax account online.6GOV.UK. Personal Tax Account: Sign In or Set Up
To cross-check the numbers, pull together:
- Your P60, which shows total pay and tax for the year from each employer.7GOV.UK. Your P45, P60 and P11D Form
- Your P45 if you changed jobs during the year.
- Your P11D, which lists the taxable value of any benefits your employer reported.8GOV.UK. Expenses and Benefits for Employers: Reporting and Paying
Add up the values on your P11D. If they total £1,350, the code is doing what it should. If they don’t, or if you no longer receive a benefit that’s still coming off your allowance, the code needs updating. Stale benefit information is one of the most common reasons people sit on the wrong code for months.
Getting the Code Changed
The quickest fix is the “Check your Income Tax” service on GOV.UK. Sign in to your personal tax account and you can report benefit changes, update your estimated income, or tell HMRC that a perk has ended. The system previews the effect on your code before you confirm.9GOV.UK. Check Your Income Tax for the Current Year
If online isn’t an option, call the HMRC income tax helpline on 0300 200 3300 (or +44 135 535 9022 from outside the UK). Once HMRC processes the change, both you and your employer will receive a new code within 15 working days.10GOV.UK. Tax Codes: If You Think Your Tax Code Is Wrong It should show up on your next payslip or the one after. If it doesn’t, check with your payroll team that the notice has reached them.
If You’ve Overpaid or Underpaid
After the tax year ends on 5 April, HMRC usually sends a P800 calculation if the code hasn’t produced the right result. The letter shows whether you owe more tax or are due a refund.4GOV.UK. Tax Overpayments and Underpayments
Overpayments can normally be claimed online, with the money arriving in five to six weeks. Underpayments are often collected by adjusting your code the following year; larger amounts may come with a Simple Assessment letter and a payment deadline. If you think the figures are wrong, contact HMRC before the deadline, not after.
HMRC doesn’t always issue a P800 automatically. If you believe you’ve overpaid and nothing has arrived, you can claim through your personal tax account or by phoning the helpline.
Scottish and Welsh Versions
If your main home is in Scotland, your code carries an S prefix, so 1122L becomes S1122L. The £11,220 tax-free figure is the same, but Scotland uses six income tax bands from 19% to 48% rather than the three bands used elsewhere in the UK.5GOV.UK. Understanding Your Employees’ Tax Codes: What the Letters Mean Welsh residents see a C prefix. Welsh rates currently match England and Northern Ireland, but the prefix exists because the Welsh Parliament can set different rates in future.