Under MTD ITSA from 6 April 2026, the annual Self-Assessment return is replaced for affected landlords by a Final Declaration. The quarterly updates through the year are operational; the Final Declaration is the legally binding statement of the year's tax position, and it carries the same 31 January deadline landlords already know. This spoke explains what the Final Declaration is, how it differs from the old SA100, and what the new annual timeline looks like in practice. It sits within [the MTD ITSA hub](/guides/mtd-itsa-landlord-2026-guide/), the pillar guide for the whole regime.
The Final Declaration is the end of a cycle the earlier spokes describe. It pulls together the figures produced by [MTD-compatible software](/blog/mtd-software-xero-freeagent-hammock/) across the year, and its accuracy depends entirely on the [digital record-keeping discipline](/blog/mtd-digital-record-keeping-rules/) applied each quarter. Clean quarterly records make the Final Declaration a confirmation; poor records make it a year-end reconstruction.
What the Final Declaration is
The Final Declaration is the taxpayer's confirmation, after the tax year ends, that the information submitted through the year is complete and correct, together with any non-MTD income, and that the resulting tax calculation is accepted. It is the point at which tax for the year is crystallised. Legally it does the job the Self-Assessment SA100 used to do: it is the binding return against which HMRC raises any assessment. The quarterly updates and End of Period Statements feed into it but are not, by themselves, the tax return.
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How it differs from the old SA100
The old model was a single annual return submitted once, usually built from a shoebox of records in the weeks before 31 January. The new model spreads the work across the year through quarterly updates and an End of Period Statement per income source, then closes it with the Final Declaration. The end deadline is the same, but the work is distributed and the figures are largely settled before year end. The Final Declaration is less a fresh data-entry exercise and more a sign-off on data already submitted.
| Feature | Old Self-Assessment (SA100) | MTD ITSA Final Declaration |
|---|---|---|
| Filings per year | One annual return | Four quarterly updates, EOPS per source, then Final Declaration |
| When work is done | Mostly before 31 January | Spread across the year, confirmed at year end |
| Record format | Paper or digital, landlord's choice | Digital records in compatible software, mandatory |
| Legally binding return | The SA100 | The Final Declaration |
| Filing deadline | 31 January following the tax year | 31 January following the tax year |
What the Final Declaration consolidates
The Final Declaration brings together the End of Period Statement figures for each MTD income source (UK property, foreign property, self-employment) and adds the income that sits outside MTD. The taxpayer confirms the complete picture so HMRC can produce the personal tax calculation across all sources.
- UK property income, finalised through its End of Period Statement.
- Foreign property income, if any, through its own End of Period Statement.
- Self-employment income, where the landlord also trades, through its End of Period Statement.
- Non-MTD income added at this stage: dividends, employment PAYE income, savings interest, and capital gains.
- Reliefs and allowances that apply across the whole tax position.
The role of the End of Period Statement
Before the Final Declaration, each MTD income source is finalised through an End of Period Statement (EOPS). The EOPS is the year-end true-up for that source: it applies accruals, prior-year adjustments and any one-off items the quarterly updates did not capture, the equivalent of the supplementary detail the old return carried per source. A landlord with UK property only has one EOPS; a landlord with UK property and a separate trade has two. The Final Declaration then sits on top of the EOPS figures and adds the non-MTD income.
It helps to think of the layers in order. The quarterly updates are running totals through the year and create no tax liability. The EOPS finalises each source with the adjustments a quarter cannot capture. The Final Declaration consolidates the finalised sources, adds the income that never went through MTD, applies reliefs and allowances across the whole position, and produces the binding tax calculation. Each layer narrows toward the single number the landlord pays by 31 January.
The new annual timeline
For a landlord inside MTD from April 2026, the 2026-27 tax year runs as follows. The four quarterly updates and the year-end statements are spread across roughly twenty-two months from the start of the tax year to the final deadline.
| Filing | Period covered | Deadline |
|---|---|---|
| Q1 update | 6 Apr to 5 Jul 2026 | 7 Aug 2026 |
| Q2 update | 6 Jul to 5 Oct 2026 | 7 Nov 2026 |
| Q3 update | 6 Oct 2026 to 5 Jan 2027 | 7 Feb 2027 |
| Q4 update | 6 Jan to 5 Apr 2027 | 7 May 2027 |
| End of Period Statement | Full 2026-27 year per source | 31 Jan 2028 |
| Final Declaration | Whole 2026-27 tax position | 31 Jan 2028 |
Is the deadline really still 31 January?
Yes. The Final Declaration for a tax year is due by 31 January following the end of that tax year, the same date the SA100 used. The 2026-27 Final Declaration is due by 31 January 2028. What changes is not the final deadline but everything before it: four quarterly updates and an End of Period Statement now precede the year-end sign-off.
Paying the tax
Tax is still paid by 31 January following the tax year end, with payments on account on 31 January and 31 July where they apply, exactly as under Self-Assessment. The quarterly updates do not generate tax payments; they are operational data, not demands. Because the figures are largely settled before year end under MTD, a landlord can see the likely liability earlier and plan the January payment with less last-minute surprise than the old annual scramble allowed.
Penalties for a late or missing Final Declaration
A missed Final Declaration earns a point under the same points-based late-submission regime that covers the quarterly updates. Points accumulate across a rolling period and, once a threshold is reached, trigger a fixed penalty, with further fixed penalties for continued lateness. Separately, tax not paid by the 31 January deadline attracts interest and late-payment penalties. The Final Declaration is the highest-stakes filing in the cycle because it is the binding return, so it should be the one a landlord diarises most carefully.
Amending a Final Declaration
As with the old Self-Assessment return, a Final Declaration can be amended after submission within the normal amendment window if an error or omission comes to light. The mechanism runs through the software and the HMRC API rather than a paper correction. Because the figures are built up across the year from digital records, post-submission amendments under MTD tend to be smaller and rarer than the wholesale corrections that annual returns sometimes needed, provided the quarterly discipline held. Where an amendment changes the tax due, interest runs on any additional tax from the original due date.
What stays the same under the new system
- The 31 January filing deadline for the binding return.
- Payments on account on 31 January and 31 July where they apply.
- The underlying tax rules: allowable expenses, Section 24 finance-cost relief, the property allowance, capital versus revenue treatment.
- The ability to use an authorised agent to file on the landlord's behalf.
- The five-year-plus record retention expectation behind the figures.
When the threshold drops below £50,000
Landlords below the £50,000 line in April 2026 should not assume the Final Declaration model never touches them. The threshold is set to drop to £30,000 from April 2027 and to £20,000 from April 2028, bringing in landlords with a single London-area property or a modest two-property portfolio. For those landlords the first Final Declaration arrives a year or two later, but the preparation is identical: digital records, compatible software, the quarterly routine, then the year-end sign-off. Treating the lower thresholds as inevitable rather than hypothetical avoids a rushed migration when the letter eventually arrives.
Can my accountant file the Final Declaration?
Yes. An [MTD-authorised accountant](/services/mtd-compliance/) can submit the quarterly updates, the End of Period Statements and the Final Declaration on the landlord's behalf, using the MTD agent authorisation rather than the legacy 64-8. Most landlords inside MTD use an agent for the Final Declaration in particular, because it is the binding return and the point at which non-MTD income and reliefs are pulled together into the full tax calculation.
Preparing for your first Final Declaration
The best preparation for the first Final Declaration happens months earlier, in the quarterly routine. Keeping clean digital records, reconciling the bank feed regularly, and categorising transactions correctly through the year means the End of Period Statements need few adjustments and the Final Declaration becomes a confirmation rather than a rebuild. Landlords who treat the quarterly updates seriously find the year-end sign-off straightforward; those who let records drift face the same January scramble MTD was designed to end.