A 1228L tax code means you can earn £12,280 in the tax year before your employer starts deducting income tax. That is £290 below the standard personal allowance of £12,570, and the gap is the whole story: HMRC has trimmed your tax-free amount to collect tax on something else, usually a workplace benefit, an earlier underpayment, or a small piece of untaxed income.1HM Revenue & Customs. Income Tax Rates and Personal Allowances
What the Number and Letter Mean
Multiply the number in a PAYE code by 10 to get your tax-free allowance for the year. 1228 gives you £12,280. Your employer spreads that allowance evenly across your pay periods, so on monthly pay roughly £1,023 comes through tax-free each month instead of the £1,047 a standard 1257L code would give you.
The L suffix simply signals that you’re on a code built from the standard personal allowance. Its practical job is administrative: when the government changes the allowance, HMRC can tell employers to adjust every L code automatically, without issuing a fresh notice for each employee.2HM Revenue & Customs. PAYE Manual – Coding: Codes: How They Are Used and Calculated: Suffix Codes: The Suffix
The standard personal allowance has been frozen at £12,570 since April 2022 and is legislated to stay there until at least April 2031.3House of Commons Library. Direct Taxes: Rates and Allowances So 1228L isn’t a default; it’s a customised code that HMRC has built for you specifically. Somebody, somewhere in your tax record, prompted that £290 reduction.
One boundary worth flagging: if you live in Scotland, a Scottish taxpayer code begins with an S (for example, S1228L) and Scottish income tax rates apply above the allowance.
Why HMRC Reduced Your Allowance by £290
The £290 cut almost always comes from one of three causes. This is the part that matters, because if the reason is wrong or out of date, you’re overpaying tax every pay period until it’s fixed.
- A taxable workplace benefit. Company cars, free fuel for personal use, private medical insurance, and similar perks are taxable. HMRC collects the tax by reducing your personal allowance rather than sending you a bill. A benefit valued at £290 would produce exactly this code.
- Underpaid tax from an earlier year. If you fell short in a previous tax year, HMRC often recovers the money by trimming your current-year allowance rather than asking for a lump sum.
- Small amounts of untaxed income. Savings interest above your personal savings allowance, or a modest side income, can be collected through your code instead of through Self Assessment.
The document that spells out which of these applies to you is your P2 Tax Coding Notice. If you don’t have the paper copy, the same breakdown is visible in HMRC’s online tax account.
How to Check Whether 1228L Is Correct
Sign in to HMRC’s “Check your Income Tax” service with your Government Gateway account. The service shows your current code and lists each adjustment HMRC has made to build it.4GOV.UK. Tax Codes: How to Update Your Tax Code Compare what you see against your own situation:
- Are the benefits listed still ones you actually receive? A company car you handed back, or medical cover that ended, shouldn’t still be reducing your allowance.
- If the reduction is for underpaid tax, has that amount already been settled?
- If untaxed income is listed, does the figure match what you’re actually earning outside PAYE?
If something on the list is wrong, report it through the same service. HMRC will issue an updated code to your employer, who will apply it from your next pay period. HMRC aims to notify the employer within 15 working days.4GOV.UK. Tax Codes: How to Update Your Tax Code
Prefer not to use the online service? You can call or write to HMRC. Have your National Insurance number, your most recent payslip, and any P60 or P45 forms in front of you before you call.
If Your Code Has Been Wrong for a While
A wrong code that runs for months adds up. After the tax year ends in April, HMRC reconciles what you earned against what your employer withheld and sends a P800 calculation if the two don’t match.
If the P800 shows you overpaid, you have to claim the refund actively through HMRC’s online service. Automatic cheques for unclaimed P800 refunds are no longer issued, so a refund left alone doesn’t turn up on its own.
If it shows you underpaid, HMRC will usually collect the shortfall by lowering your code for the following year, spreading the cost over 12 months. Larger shortfalls that can’t be collected this way trigger a direct contact from HMRC about payment.
You have four years from the end of the relevant tax year to claim an overpayment refund. Miss that window and the year closes. If you suspect your 1228L code has been wrong for more than one year, check each year separately in the online service; more than one refund may be waiting.
Why 1228L May Disappear After April 2027
From April 2027, employers will be required to report benefits in kind through payroll software in real time, a change known as mandatory payrolling. At present, employers report most benefits annually on a P11D and HMRC adjusts your code the following year to collect the tax. Under the new system, the value of the benefit is added straight to your taxable pay in each period it’s provided.5GOV.UK. Technical Note: Mandating the Reporting of Benefits in Kind and Expenses Through Payroll Software: An Update
Once that takes effect, HMRC will strip benefit-related adjustments out of tax codes. If your 1228L exists because of a taxable benefit, you would most likely revert to 1257L after April 2027. Your take-home pay wouldn’t rise as a result, because the benefit would then be taxed directly through payroll instead. The change was originally set for April 2026 and was pushed back by a year to give employers and software providers more time. If your code came from an underpayment or untaxed non-employment income rather than a benefit, this reform won’t affect you.