MTD final declaration: what you submit at the end of the tax year
Short answer: The final declaration is the last step of your tax year under Making Tax Digital for Income Tax. After your fourth quarterly update, you make year-end adjustments, add other income, check HMRC’s tax calculation and declare it is correct. It is due by 31 January after the tax year ends, and you do it in your MTD software.
Not sure whether you are in MTD yet? Use the MTD checker.
What the final declaration is
GOV.UK calls this step “submit your tax return”. HMRC’s developer guidance uses “final declaration” for the same thing, which is the name you will see in many articles. GOV.UK describes Making Tax Digital as a new way to do Self Assessment, and says submitting the return generates your Self Assessment tax bill.
Quarterly updates are summaries of business income and expenses. They are not tax returns. The final declaration is the point where HMRC works out your tax for the year from everything it holds, and you confirm it.
You do this in your compatible software. GOV.UK says you must view and check the tax calculation, then declare that the information is correct and complete to the best of your knowledge.
What happened to the End of Period Statement
Before the current design, the plan included an End of Period Statement (EOPS) for each business. It has been dropped, and the current rules, the Income Tax (Digital Obligations) Regulations 2026, do not include it. You do not send an EOPS: your fourth quarterly update and the final declaration cover the year-end.
Deadline
The return is due by 31 January after the end of the tax year. You can submit early: GOV.UK gives the example that a 2025-26 return can be sent from 6 April 2026.
| Tax year | Who it applies to first | Final declaration due |
|---|---|---|
| 2026-27 | Income over £50,000, in MTD from 6 April 2026 | 31 January 2028 |
| 2027-28 | Income over £30,000, in MTD from 6 April 2027 | 31 January 2029 |
The first quarterly update for the 2027 group is due on 7 August 2027. The full list is on MTD deadlines, and the group is explained in MTD from April 2027.
What you add at the end of the year
GOV.UK sets out the order. After your fourth quarterly update, HMRC holds your income and expense data for the year. You then adjust it, add other income, check it and submit.
Adjustments to self-employment and property income
GOV.UK lists these kinds of adjustment:
- Disallowable expenses: reduce a category total to remove the part you cannot claim, for example the personal share of a phone bill.
- Reliefs and allowances: for example rent-a-room relief, which covers up to £7,500 a year, or half that if shared, and the trading income allowance.
- Capital allowances: record your claim before you submit. HMRC does not process it until you submit the return.
- Accounting adjustments: only if you do not use the default cash basis, such as prepayments and accruals.
- Accounting period adjustments: only if your accounting period is not 6 April to 5 April.
GOV.UK says you may need to resend your fourth update to correct errors, add joint property expenses you left out or record Rent-a-Room income. Details of what goes in each update are in what goes in a quarterly update.
Other income and gains
HMRC adds some items itself if it holds the information. GOV.UK lists:
- employment (PAYE) income
- state, private and occupational pension income
- other taxable state benefits
- Construction Industry Scheme deductions
- Capital Gains Tax on residential property disposals
- Marriage Allowance claims
- student loan plan type and postgraduate loan
You must add these yourself:
- savings interest
- dividends, including from your own company
- your share of partnership profits as an individual partner
- payrolled benefits in kind not subject to Class 1A National Insurance
- any other income or gains HMRC has not added
Check HMRC’s entries as well as adding your own. Corrections you make in the software overwrite the earlier figures. If you have both a trade and rental income, see self-employment and property together.
GOV.UK also says you cannot claim a tax refund through the return.
Does it replace the Self Assessment return?
It is still your Self Assessment return, sent a different way. What changes is how you report. In MTD you submit your tax return through MTD software instead of the old online return, the deadline is the same 31 January, and the bill it produces is a Self Assessment bill.
Paying the tax
MTD does not change how or when you pay. GOV.UK says the same dates apply:
| Date | What is due |
|---|---|
| 31 January after the tax year | Balancing payment: your total bill minus payments on account already made |
| 31 January | First payment on account (half of last year’s tax) |
| 31 July | Second payment on account |
You do not need payments on account if last year’s bill was under £1,000, or if more than 80% of it was paid outside Self Assessment, for example through your tax code.
Penalties
Penalties for a late final declaration are points-based. GOV.UK says you get one point for each missed tax return deadline. At 4 points you receive a £200 penalty, and £200 more for each further missed deadline. The pause on points for quarterly updates in 2026-27 does not cover a late tax return. See MTD penalties.
Late payment is separate and not points-based, and it does not apply to payments on account. For 2026-27, GOV.UK sets out a 3% penalty on tax still unpaid at day 15, a further 3% at day 30, then 10% a year from day 31. For 2027-28 the two charges are 4% each. In your first year under the new penalties there is no charge for the first 30 days. Interest is charged separately from the first day the payment is late.
Example timeline: a landlord in the April 2027 group
Example: Alex, a landlord. Alex let two flats and had £34,000 of rent on the 2025-26 return, so Alex joins MTD on 6 April 2027. This is an example with round numbers.
| When | What Alex does |
|---|---|
| 7 August 2027 | First update, 6 April to 5 July 2027 |
| 7 November 2027 | Second update, cumulative from 6 April |
| 7 February 2028 | Third update |
| 7 May 2028 | Fourth update, covering the whole 2027-28 year |
| May to December 2028 | Check adjustments, add savings interest from a bank account, check HMRC’s figures, resend the fourth update if records need correcting |
| By 31 January 2029 | Check the tax calculation, make the declaration, pay the balancing payment and first payment on account |
| 31 July 2029 | Second payment on account |
Alex can send the declaration as soon as the fourth update and adjustments are done, instead of waiting for January. How updates build on each other is explained in cumulative quarterly updates.
Changing it afterwards
GOV.UK says you can change the return in your software within 12 months of the submission deadline. If you spot an error in your digital records before you submit, correct it in the records, not in the return.
Tools like SendMTD, which is still being built and is not HMRC recognised, aim to prepare the bank-statement totals for the quarterly updates that feed this step. Whatever you use, the final declaration must be made through software that works with MTD.
Sources
- Submit your tax return (Use Making Tax Digital for Income Tax)
- Adjust your self-employment and property income
- Send quarterly updates
- Using Making Tax Digital for Income Tax for the first time
- Penalties for Making Tax Digital for Income Tax
- Payments on account
- The Income Tax (Digital Obligations) Regulations 2026
- Find out if and when you need to use Making Tax Digital for Income Tax
This guide is general information, not tax or legal advice. Rules can change: check GOV.UK or speak to an accountant about your situation. SendMTD is not affiliated with HMRC.