A 1350L tax code means you have £13,500 of tax-free income for the year, which is £930 more than the standard Personal Allowance of £12,570.1GOV.UK. Income Tax Rates and Personal Allowances That extra £930 almost always comes from employment expense reliefs HMRC has added to your code, such as flat-rate deductions for uniform maintenance, working-from-home relief, or approved professional subscription fees.
How the Code Is Built
Every UK tax code splits into a number and a letter. The number is your annual tax-free allowance divided by ten, so 1350 translates to £13,500. Your employer spreads that allowance across each pay period, deducting tax evenly rather than in a single hit.2GOV.UK. Tax Codes
The L suffix means you’re entitled to the standard tax-free Personal Allowance with no unusual adjustments applied (no Marriage Allowance transfer, no Scottish rate flag).3GOV.UK. What Your Tax Code Means If the standard allowance were your only entitlement, your code would read 1257L. The 1350L figure tells you HMRC has approved £930 of extra reliefs on top of that baseline.
Where the Extra £930 Comes From
Three sources account for most 1350L codes: flat-rate job expenses, professional subscriptions, and working-from-home relief. HMRC bundles all approved reliefs into one adjusted code rather than issuing a separate notice for each.
Flat-Rate Job Expenses
If your work requires washing or maintaining a uniform, buying specialist tools, or replacing protective clothing, HMRC sets fixed deduction amounts by industry rather than asking you to track receipts.4GOV.UK. Check How Much Tax Relief You Can Claim for Uniforms, Work Clothing and Tools The approved amount depends on your occupation. A healthcare worker, a mechanic, and a construction labourer are each on different rates.
Professional Subscriptions
Membership fees paid to an HMRC-approved professional body or learned society qualify for relief when the membership is relevant to your job and you pay the fees yourself.5GOV.UK. Claim Tax Relief for Your Job Expenses – Professional Fees and Subscriptions HMRC publishes the approved list. Fees your employer pays on your behalf don’t count, and lifetime memberships are excluded.
How the Reliefs Combine
A 1350L code often reflects several reliefs stacked. Someone claiming a £60 flat-rate uniform deduction, a £312 working-from-home allowance, and several hundred pounds in professional body fees could easily add up to the £930 gap between 1257L and 1350L.
Checking Your 1350L Is Right
Tax codes go wrong more often than people assume. HMRC might carry forward a relief you no longer qualify for, miss a new claim, or work from an outdated estimate of untaxed income. A code that’s too low means you overpay every payday; a code that’s too high leaves you facing an underpayment bill later.
The quickest check is the “Check your Income Tax” online service, which shows your current code, estimated income, and every relief HMRC has applied.6GOV.UK. Check Your Income Tax for the Current Year Sign in with either a Government Gateway account or a GOV.UK One Login; both currently work, though One Login will eventually replace Government Gateway.7GOV.UK. HMRC Online Services – Sign In or Set Up an Account
Compare what the service shows against your reality. Do the expense amounts match what you actually pay? Is your professional body still on the approved list? Are you still doing the job that qualified you for a flat-rate deduction? If anything is out of date, update it through the service. If you can’t use the online tool, call HMRC. When you’ve just started a new job, HMRC suggests waiting 35 days for your new employer’s payroll data to come through before making contact.8GOV.UK. If You Think Your Tax Code Is Wrong
Adding or Updating an Expense Claim
If you have qualifying expenses that aren’t yet in your code, claim them through your Personal Tax Account. Have your recent payslips or P60 to hand for accurate income figures, and total up the professional fees, uniform costs, or other work-related outgoings you want to claim.
Sign in to the “Check your Income Tax” service, review your details, and add or update your employment expense claims.8GOV.UK. If You Think Your Tax Code Is Wrong After you submit, HMRC updates your code and notifies both you and your employer within 15 working days. Monthly-paid workers should see the new code on their next payslip or the one after. Weekly-paid workers should see it by the third payslip.
Backdating a Claim You Missed
If you’ve been entitled to a relief for years but never claimed it, you can backdate for up to four tax years after the end of the year in which you overpaid. A claim for the 2022/23 tax year (which ended 5 April 2023) must reach HMRC by 5 April 2027. After that, the year is closed.
The four-year rule covers flat-rate expenses, professional subscriptions, incorrect tax codes, Marriage Allowance, and working-from-home relief. The refund depends on your tax rate: a basic-rate taxpayer saving 20% on a £60 annual deduction gets £12 back per year. The numbers grow quickly when multiple reliefs stack across several years.
When You Wouldn’t See a 1350L Code
Some reliefs change the letter rather than adjusting the number. If you were expecting 1350L and see something else, this is often why.
Marriage Allowance is the common one. When a lower-earning partner transfers £1,260 of their Personal Allowance, the transferring partner’s code takes an N suffix and the receiving partner’s code takes an M suffix.3GOV.UK. What Your Tax Code Means The transfer reduces the recipient’s tax by up to £252 a year.9GOV.UK. Marriage Allowance A recipient’s code would read something like 1257M rather than 1350L.
If Your Income Crosses £100,000
The standard Personal Allowance has been frozen at £12,570 since April 2022 and will remain there until at least April 2031. Earning above £100,000 triggers a taper that cuts your allowance by £1 for every £2 of adjusted net income above the threshold.1GOV.UK. Income Tax Rates and Personal Allowances By £125,140, your allowance reaches zero.
The taper applies regardless of the expense reliefs sitting inside your code. A 1350L code built on £930 of job expenses still gets reduced once your income moves into the taper band, and the effective marginal rate in that band is 60% because you lose allowance and pay tax on the newly exposed income at the same time. Pension contributions and Gift Aid donations reduce adjusted net income and can preserve some of the allowance.