Freelancer Tax Return Checklist UK

Your 2025/26 Self Assessment tax return is due online by 11:59pm on Sunday 31 January 2027, and any tax you owe is due the same day. That is the one date this whole checklist hangs on. Everything below is the work that stands between you and that deadline: the papers to gather, the expenses freelancers most often forget to claim, the payment-on-account trap that adds half again to a first-year bill, and what happens if you miss it. Work through it in order and you will file once, pay what is due in January, and know exactly what is still to come in July. We checked every date and rate below against GOV.UK on 9 November 2026.

This is general information, not legal or financial advice. If the amount is large or the situation is disputed, get proper professional advice.

The dates that matter

There are only a few dates, but two of them have already passed, which is exactly why this checklist starts here. The tax year in question ran from 6 April 2025 to 5 April 2026. If you earned freelance income in that year and it was over the £1,000 trading allowance, you need to file.

Two details in that table catch people out. First, if you registered after 5 October 2026, HMRC gives you a different filing deadline, three months from the date of its letter or email, but the payment date does not move: the tax is still due by 31 January 2027. Second, 31 January 2027 is a Sunday. Filing online is fine on a Sunday, but paying is not automatic: if you pay by bank transfer using Bacs, allow three working days, so send it by Tuesday 26 January at the latest. Faster Payments and debit card payments reach HMRC the same or next day, including weekends, so those still work on the Sunday itself. There is more on payment methods below.

Before you start: gather these

A tax return is mostly a gathering exercise. Get the papers together before you open the form and the filing itself takes an evening. You need:

• Your Unique Taxpayer Reference (UTR), the 10-digit number HMRC posted you when you registered, and your Government Gateway user ID and password. No UTR, no return, so if you registered and it never arrived, chase HMRC now rather than in January.
• Every invoice you issued in 2025/26, or at least a complete list of them with dates and amounts. If you use cash basis accounting, which has been the default for sole traders since the 2024/25 tax year, you count income when you received it, not when you invoiced it. That means an invoice dated March 2026 but paid in April 2026 belongs in next year’s return, and an invoice from March 2025 paid in April 2025 belongs in this one. Check your bank statements against your invoices and find the gaps before HMRC does.
• Your business bank statements for the full year, plus any business PayPal or Stripe statements if clients paid you that way.
• Receipts and records for every expense you plan to claim. You do not send them to HMRC, but you must be able to show them if asked, and you must keep them for at least five years after the 31 January submission deadline, which for this return means until at least the end of January 2032.
• Your P60 or P45 if you also had employed income in the year, and any P11D for benefits.
• Pension contribution statements and Gift Aid records. Both can reduce your bill, and both are easy to forget because the money left your account months ago.
• Student loan statements, if you have a loan. Repayments are worked out from your income and go on the return.
• CIS statements, if any of your work was paid under the Construction Industry Scheme with tax already deducted.

If any of that is missing, start with the bank statements. They are the one record that reconstructs almost everything else: income in, expenses out, and the dates that decide which tax year each item belongs to.

The expenses freelancers commonly miss

This is where a checklist earns its keep. Many freelancers claim the obvious costs, the laptop, the software, and then leave hundreds of pounds unclaimed in the small, boring corners. Every item below is an allowable expense under GOV.UK’s rules for the self-employed, provided it was wholly and exclusively for the business. Where there is a limit or a trap, it is stated next to the item.

Working from home. You have two ways to claim this, and you should run both before you choose. The simple way is HMRC’s flat rate: £10 a month if you work 25 to 50 hours a month from home, £18 for 51 to 100 hours, and £26 for 101 hours or more. You need at least 25 hours in a month to claim anything for that month, and the flat rate does not cover your phone or broadband. The other way is to claim a fair proportion of your actual costs: heating, electricity, Council Tax, mortgage interest or rent, worked out by rooms or by time. If you work from home most days, the actual-costs method is usually worth more than the £312 a year the top flat rate gives you, but it needs real numbers and a method you can defend. The GOV.UK simplified expenses checker compares the two methods for your figures.

Business mileage. If you drive for work, the 2025/26 mileage rate is 45p a mile for the first 10,000 business miles in the year, and 25p a mile after that. That rate covers cars and vans. It does not cover commuting from home to a regular workplace, and it does not cover fines or parking tickets. Keep a log: date, destination, purpose, miles. A log written from memory in January is worth far less than one kept as you went, but a reconstructed log from your calendar and invoices is still better than no claim at all. Our mileage calculator works out the deductible amount from your miles and tax year, and the 2026/27 rate rises to 55p for the first 10,000 miles (25p after that, unchanged), so check you are using the right year’s figure.

Phone and broadband. Claim the business proportion only. HMRC’s own example is a £200 annual phone bill split £130 personal and £70 business: you claim £70. Work out your proportion honestly, write it down, and use the same method every year.

Subscriptions and professional memberships. Trade journals, professional body fees, and the software you pay for monthly all count, including the tools you use to run the business rather than do the work. Check your bank statement for the small monthly debits you stopped noticing: the invoicing app, the cloud storage, the stock photo subscription. They add up.

Training courses. Refresher courses and training that keeps your current skills up to date are allowable. Training for a new business or a new line of work is not. The line is whether the course improves what you already do, or starts something different.

Insurance. Professional indemnity and public liability premiums are allowable expenses, as are business bank charges and interest on business loans. Note that loan repayments themselves are not claimable, only the interest.

Accountancy fees. Fees for business advice are allowable, but HMRC is explicit that you cannot claim the cost of preparing and submitting your Self Assessment tax return itself. If your accountant’s bill mixes the two, ask them to split it.

Bad debts. If a client never paid and you are certain they never will, you can write the amount off, but only if you use traditional accounting. Under cash basis you never counted the money as income in the first place, so there is nothing to write off. If the unpaid invoice is still being chased, it is not a bad debt yet. Our MCOL fee estimator shows what it costs to take an unpaid invoice to court, which is the step before writing it off.

What you cannot claim. Everyday clothing, even if you only wear it for work. Entertaining clients, including lunch during a meeting. Fines and penalty charges. Travel between home and work. And the £6 a week homeworking allowance you may have heard about is for employees, not for the self-employed; as a sole trader you use the flat rates or actual costs above, not the employee allowance.

Trading allowance or expenses: pick one. If your gross trading income was over £1,000, you can either claim the £1,000 trading allowance instead of your actual expenses, or claim your actual expenses. You cannot do both. Add up your expenses first: if they come to more than £1,000, claim them; if they do not, take the allowance. Note that the allowance rises to £3,000 from 6 April 2027, which affects your 2027/28 return, not this one. Our trading allowance guide explains the change in full.

Work out what you will owe

Before you file, work out the bill, because the number decides how you pay and whether you need a payment plan. The arithmetic for a sole trader has three parts: Income Tax, Class 4 National Insurance, and, for low profits, a decision about voluntary Class 2.

Income Tax for 2025/26, for England, Wales and Northern Ireland, works like this: the first £12,570 of profit is covered by your Personal Allowance and taxed at 0%. The next £37,700 of taxable income is taxed at 20%. Income above £50,270 in total is taxed at 40%, and above £125,140 at 45%. Above £100,000 your Personal Allowance shrinks by £1 for every £2 over, and disappears at £125,140. Scotland sets its own bands, so Scottish readers should check the Scottish rates on GOV.UK.

Class 4 National Insurance is 6% on profits between £12,570 and £50,270, and 2% on profits above £50,270. It is collected through Self Assessment alongside your Income Tax. Class 2 is different: if your profits were £6,845 or more in 2025/26, Class 2 is treated as paid and the year counts towards your State Pension at no extra cost. Below £6,845 you can pay voluntary Class 2 at £3.50 a week to protect your pension record. One small trap for anyone checking GOV.UK today: the current page shows £7,105 and £3.65 a week, but those are the 2026/27 figures. The 2025/26 return uses £6,845 and £3.50.

A worked example makes the shape of the bill clear. Take a freelancer whose profit for 2025/26, after expenses, was £45,000, who is filing Self Assessment for the first time, and assume this is their only taxable income:

• Income Tax: (£45,000 minus £12,570) at 20% = £6,486.00
• Class 4 National Insurance: (£45,000 minus £12,570) at 6% = £1,945.80
• Total bill for 2025/26: £8,431.80

That is the tax for the year. But it is not the amount due on 31 January, because of payments on account, which is the next section.

Payments on account: the bill behind the bill

Payments on account are HMRC’s way of collecting next year’s tax in advance, in two instalments. You have to make them if your bill for the year just ended was £1,000 or more and less than 80% of your tax was collected at source, for example through PAYE. Each instalment is half of the previous year’s bill, and they fall due on 31 January and 31 July.

For a first-year filer the effect is sharp. Our £45,000 example above owes £8,431.80 for 2025/26, and the first payment on account for 2026/27, half the bill at £4,215.90, falls due on the same day. So the amount payable on 31 January 2027 is £12,647.70: the full year’s bill plus half of next year’s, or 150% of one year’s bill on a single day. The second payment on account of £4,215.90 follows on 31 July 2027. Our payment on account estimator works out your exact figures from your profit, including this first-year warning.

If you expect your income to fall in 2026/27, you can ask HMRC to reduce your payments on account, either online through your tax account or by sending form SA303. Do not reduce them on a guess. If you cut them too far and your bill comes in higher than expected, HMRC charges interest on the difference, at 8% a year from 24 November 2026. Reduce them only when you have a real reason, such as a lost contract or a quiet order book you can point to.

Paying on 31 January: mind the Sunday

Paying is a separate job from filing, and the deadline is the same. HMRC must receive the money by 11:59pm on 31 January 2027. How long the payment takes depends on the method:

• Same or next day: Faster Payments through online or telephone banking, debit card online (no fee for a personal debit card), or paying through your online bank account. These work on the Sunday itself.
• Same working day only: CHAPS. It does not operate on a Sunday, so if you pay this way, send it by Friday 29 January 2027 at the latest.
• Three working days: Bacs, or a Direct Debit you have already set up with HMRC. Send these by Tuesday 26 January at the latest.
• Five working days: a Direct Debit you are setting up for the first time.

When you pay, use your 11-character payment reference: your 10-digit UTR followed by the letter K. The wrong reference can delay the payment or put it against the wrong bill, so copy it from your HMRC online account rather than from memory.

There are two ways to make the bill smaller on the day. If you also have PAYE income and your bill is under £3,000, HMRC can collect it through your tax code, provided you have enough PAYE income for HMRC to collect it from, but only if you file online by 30 December 2026. And if you would rather spread the cost before the deadline, a Budget Payment Plan lets you pay weekly or monthly towards the bill in advance through your HMRC account. Neither option helps if you leave it until the last week, so decide now which one you are using.

If you cannot pay in full

File anyway. This is the single most useful sentence in this article. The penalty for filing late and the penalty for paying late are separate, so filing on time stops one set of charges even if the money is not there yet. A return filed on time with an unpaid bill costs you interest and late payment penalties; a return filed late costs you those plus the filing penalties below.

If the bill is already overdue, HMRC’s Time to Pay arrangement lets you clear it in monthly instalments. You can set it up yourself online if you owe £30,000 or less, your returns are up to date, you have no other tax debts or HMRC payment plans, and you apply within 60 days of the payment deadline. Outside those limits you need to phone HMRC. Interest keeps running on the outstanding balance throughout the arrangement, at 8% a year from 24 November 2026, so the sooner you set it up the less it costs. If you agree a plan before the first late payment penalty date, that penalty can be avoided; miss an instalment and the suspended penalties become payable.

What missing the deadline costs

The filing penalties are automatic and they stack. File one day late and you owe £100, even if you owe no tax at all. After three months, HMRC adds £10 a day for up to 90 days, a maximum of £900. After six months, a further penalty of 5% of the tax due or £300, whichever is greater. After twelve months, the same again. A return filed six months late with £2,000 of tax due would already carry £100 plus £900 plus £300 in filing penalties, before any payment penalties.

Paying late is charged separately: 5% of the unpaid tax at 30 days, again at 6 months, and again at 12 months, plus interest from 1 February 2027 on the amount owed. HMRC’s late payment interest rate is the Bank of England base rate plus 4%, which is 8% a year from 24 November 2026, following the base rate rise to 4% on 5 November.

If you had a genuine reasonable excuse, a serious illness, a bereavement, a failure in HMRC’s own systems, you can appeal a penalty. “I forgot” and “I was busy” are not reasonable excuses in HMRC’s book, and the appeal has to be made promptly once the excuse no longer applies.

Making Tax Digital: does it change this return?

If you are in Making Tax Digital for Income Tax, the £50,000 income wave that started in April 2026, you are already sending HMRC quarterly updates. Those updates do not replace this return. HMRC has confirmed that customers signed up to Making Tax Digital still need to submit a Self Assessment tax return and pay any tax owed by 31 January 2027. From April 2027 the threshold drops to £30,000, which pulls more freelancers into quarterly updates; our MTD £30,000 guide covers that wave in detail, and our MTD quarterly update checker tells you what to enter for the current quarter.

Your file-week checklist

Print this section and work it top to bottom in the week you file:

1. Confirm your UTR and Government Gateway login work. Do this a week early, not on the day.
2. Reconcile income. Match every invoice to a bank receipt for 6 April 2025 to 5 April 2026, under cash basis unless you use traditional accounting.
3. Total your expenses and check each one against the missed-items list above. Decide trading allowance or actual expenses, whichever is higher.
4. Work out the bill with the rates in this article, or run the numbers through our payment on account estimator, and check whether payments on account apply to you.
5. File online and save the submission receipt with its reference number.
6. Pay by the right method for the day. Faster Payments or debit card if it is the weekend; Bacs only if you sent it by Tuesday 26 January. Use your UTR followed by K as the reference.
7. Diary the next two dates: 31 July 2027 for the second payment on account, and 31 January 2028 if you need to amend the return.
8. File the records away and keep them until at least the end of January 2032.

The return itself is not the hard part. The hard part is the two weeks of gathering that comes before it, and the bill that is bigger than expected because of payments on account. Start the gathering now, while there are still eleven weeks to the deadline, and January becomes a formality instead of a scramble.

Quick answers

What is the Self Assessment deadline for the 2025/26 tax year?

The online return and any tax you owe are due by 11:59pm on 31 January 2027. The paper return deadline, 31 October 2026, has already passed. If you want a bill under £3,000 collected through your PAYE tax code, file online by 30 December 2026.

I earned less than £1,000 from freelancing. Do I still need to file?

Not for that income alone. The £1,000 trading allowance means gross trading income at or below £1,000 does not need to be reported. Above £1,000 you must register and file, and you can claim either the allowance or your actual expenses, whichever is higher. Other income, such as employment or rental income, has its own rules and may still require a return.

What happens if I file late but owe no tax?

You still get the £100 late filing penalty. It applies even if you owe nothing or you paid on time. After three months HMRC adds £10 a day for up to 90 days, then further penalties at 6 and 12 months. Filing on time is worth doing even when the bill is zero.

Can I reduce my payments on account?

Yes, if you know your 2026/27 tax will be lower than your 2025/26 bill. You can do it online through your HMRC tax account or by sending form SA303. Only reduce them for a real reason, such as a lost contract, because if your bill comes in higher than expected HMRC charges interest on the difference.

How long must I keep my tax records?

If you are self-employed, keep your records for at least five years after the 31 January submission deadline of the relevant tax year. For the 2025/26 return that means until at least the end of January 2032. HMRC can ask to see them at any point in that period.

Sources

• GOV.UK, Self Assessment tax returns: deadlines: the 31 January 2027 online deadline, the 30 December PAYE code date, and the 5 October registration rule.
• GOV.UK, Self Assessment tax returns: penalties: the £100 filing penalty, the daily and percentage penalties, and the late payment penalties.
• GOV.UK, Pay your Self Assessment tax bill: payment methods and clearing times, the weekend rule, and the UTR plus K reference.
• GOV.UK, Understand your Self Assessment tax bill: payments on account: who pays them, how they are calculated, and how to reduce them.
• GOV.UK, Self-employed National Insurance rates: Class 4 rates and the Small Profits Threshold.
• GOV.UK, Rates and allowances: National Insurance contributions: the 2025/26 Small Profits Threshold of £6,845 and the voluntary Class 2 rate of £3.50 a week.
• GOV.UK, Expenses if you’re self-employed: allowable expenses, what you cannot claim, and the home-working rules.
• GOV.UK, Simplified expenses if you’re self-employed: the £10, £18 and £26 monthly flat rates for working from home.
• GOV.UK, Business records if you’re self-employed: the five-year record-keeping rule and cash basis as the default.
• GOV.UK, HMRC interest rates for late and early payments: late payment interest of 8% from 24 November 2026.
• GOV.UK, Self Assessment tax returns: who must send a tax return: the £1,000 trading allowance and who needs to file.
• GOV.UK, If you cannot pay your tax bill on time: setting up a payment plan to pay in instalments.
• HMRC, Starting early is key to less stress around Self Assessment: HMRC’s October 2026 reminder of the 31 January 2027 deadline and the MTD position.

We verified the GOV.UK links above on 9 November 2026. Tax rates and thresholds are for the 2025/26 tax year (England, Wales and Northern Ireland) unless stated otherwise; re-check them on GOV.UK before acting, as rates change.