Last checked 19 October 2026
Quick answer
Under Making Tax Digital (MTD) for Income Tax, you still send one tax return a year, through your compatible software rather than HMRC’s old online return. After your fourth quarterly update, you make any adjustments, such as removing disallowable expenses or claiming capital allowances, add your other income, check the figures HMRC has added, then submit. The deadline stays 31 January after the end of the tax year, and payment dates don’t change.
This is general information, not tax advice. Check GOV.UK or speak to an accountant about your situation. Why we say this.
Quarterly updates get most of the attention, but the tax return is still where your tax bill is settled. HMRC’s guidance calls this stage “finalising your Income Tax position”. This guide walks through the steps in the order HMRC sets them out.
If you start MTD on 6 April 2027, your first MTD tax return will be for the 2027 to 2028 tax year, due by 31 January 2029. Before that, GOV.UK says you still submit a normal Self Assessment return for 2026 to 2027, due by 31 January 2028.
The end-of-year steps at a glance
- Send your fourth quarterly update, covering the whole tax year.
- Make any adjustments to your self-employment and property totals.
- Add your other income and gains, and check what HMRC has added.
- Check the tax calculation in your software.
- Submit your tax return by declaring it’s correct and complete.
- Pay your bill by the usual date.
Step 1: the fourth quarterly update
HMRC says that once you’ve sent your fourth quarterly update, it has details of all your self-employment and property income and expenses for the tax year, for every business. Our guide to MTD quarterly updates explains what each update contains. If you spot an error after sending it, HMRC says you may need to correct your records and resend the fourth update before making adjustments.
Step 2: adjustments
HMRC’s Adjust your self-employment and property income guidance says you may need to adjust the figures you’ve sent before you complete your return. It lists:
- claiming reliefs or allowances, such as the trading income allowance
- tax adjustments, such as removing expenses you can’t claim, known as disallowable expenses
- accounting adjustments, such as prepayments or accruals, if you use traditional accounting
- adjustments for your accounting period, if it doesn’t match the tax year
- capital allowances, which let you deduct the cost of capital assets, such as plant and machinery
HMRC says you make most adjustments by updating the annual total for an expense category in your software, so you don’t need to change each transaction.
HMRC’s example
If you use one phone for business and personal calls, you reduce the category total for “phone, fax, stationery and other office costs” so you’re only claiming the business part.
If you use cash basis
HMRC says cash basis is the default accounting method for self-employment and property income, and you don’t need to make accounting adjustments, such as for prepayments, if you use it.
If your accounting period isn’t 6 April to 5 April
HMRC says that if your accounting period matches the tax year, you don’t need any accounting period adjustments. If it runs from 1 April to 31 March and you selected calendar update periods from the start, HMRC says you won’t need this type of adjustment either. Other accounting dates need extra adjustments, and HMRC says it will publish more guidance on some of these. An accountant can help here.
Capital allowances
HMRC says you use your software to record a capital allowances claim before you submit your return. Your software may let you record it during the year, but HMRC won’t process the claim until you submit your tax return.
Step 3: other income and gains
HMRC’s Submit your tax return guidance says all your other taxable income and gains for the year must be in your software before you submit.
| HMRC says it will add | You’ll need to add |
|---|---|
| Employment (PAYE) income | Savings interest |
| Student and postgraduate loan details | Your share of partnership profit |
| State, private and occupational pensions | Dividends |
| Other taxable state benefits | Certain payrolled benefits in kind |
| CIS subcontractor deductions | Any other income or gains not added automatically |
| Capital Gains Tax on residential property disposals | |
| Marriage Allowance claims |
Source: Submit your tax return (GOV.UK). HMRC says you must check the information it adds before you submit, and if it doesn’t have everything, you’ll need to add it yourself.
Step 4: check the calculation
HMRC says you must add all income sources and gains and check all the information is correct and complete before submitting. If something’s wrong, you correct it in your software, and the correction overwrites the earlier information.
If there’s a problem with your software that you can’t fix, HMRC says to contact your software provider first. If they can’t resolve it and you still can’t confirm your calculation or submit, HMRC says to tell it as soon as possible.
Step 5: submit
HMRC sets out three steps:
- Go into your software and confirm you’re ready to submit.
- View and check the tax calculation is correct.
- Submit by declaring that your information is correct and complete to the best of your knowledge.
Your software then shows a message confirming your return has been submitted.
Using an accountant
HMRC says only your main agent can submit your tax return under MTD. Before submitting, the agent must share a copy with you and get your written confirmation that it’s correct and complete. Our guide to accountant or DIY explains main and supporting agents.
The deadline
HMRC says you must submit your tax return by 31 January following the end of the tax year, but you can submit earlier. Its example: you can submit your 2025 to 2026 return any time from 6 April 2026 to 31 January 2027. Missing the deadline means a late submission penalty point. Our guide to MTD penalties explains how points work.
Step 6: paying
HMRC says the information you give generates your Self Assessment tax bill for the year, and that MTD won’t change the way you pay tax or the dates payments are due. Our guide to MTD quarterly deadlines lists the payment dates around your first MTD year.
Refunds and changes
- Refunds: HMRC says that if you think you’re due a refund, you can’t claim it in your MTD tax return. Its Help and support page explains how to claim.
- Changing a return: HMRC says you can change a submitted return within 12 months of the submission deadline, using your compatible software. Your online account will then show an updated calculation.
- Before submitting: if the change relates to your digital records, HMRC says to correct the records rather than the return.
Frequently asked questions
Is the MTD tax return the same as Self Assessment?
It still produces your Self Assessment tax bill, but under MTD you complete and submit it through compatible software. HMRC calls it a tax return in its guidance.
When can I submit my first MTD tax return?
If you start on 6 April 2027, your first MTD return covers 2027 to 2028. HMRC’s pattern means you can submit from 6 April 2028, and the deadline is 31 January 2029.
Do payment dates change under MTD?
No. HMRC says MTD won’t change the way you pay tax or the dates payments are due.
Can my bookkeeper submit my tax return?
Only your main agent can submit your return under MTD, according to HMRC.
Sources
All checked on 19 October 2026.
- Submit your tax return (GOV.UK)
- Adjust your self-employment and property income (GOV.UK)
- Send quarterly updates (GOV.UK)
- Help and support (GOV.UK)
- Find out if and when you need to use Making Tax Digital for Income Tax (GOV.UK)
Where to check
What changed. : . 19 October 2026: First published.
