What UK tax deadlines are coming before the end of 2026? September to December, in order

Last verified: 26 August 2026, against the cited gov.uk and legislation.gov.uk sources.

Running throughout: quarterly VAT returns

What it is. If you're VAT-registered and file quarterly, the deadline for submitting each return — and for the payment clearing HMRC's account — is one calendar month and 7 days after the end of the accounting period (gov.uk: VAT return deadlines). Which quarters you're on depends on your stagger, so for this window:

Who it applies to. Quarterly VAT filers. Your VAT online account shows your exact due dates and when payment must clear (gov.uk) — the table above is the standard pattern, and payment deadlines don't move for weekends or bank holidays, so pay early enough to clear.

If missed. Each late return earns a penalty point; for quarterly filers the threshold is 4 points, at which you get a £200 penalty, plus £200 for each further late submission while at the threshold (gov.uk: VAT late-submission penalties).

What to do now. Open your VAT online account once and note your two due dates before February — then they're diary entries, not surprises.

5 October 2026 — tell HMRC you need to file for 2025-26

What it is. You must tell HMRC by 5 October 2026 if you need to complete a tax return for the previous tax year — 6 April 2025 to 5 April 2026 — and haven't filed one before or didn't need to file last year (gov.uk: register for Self Assessment). This is the registration deadline, not the filing deadline: you're just getting on HMRC's list and getting your UTR.

Who it applies to. Anyone whose 2025-26 activity newly tips them into Self Assessment — typically a side hustle whose gross trading income passed the £1,000 trading allowance, a first rental property, or a first year of self-employment. Our first Self Assessment guide walks through whether you actually need to file at all.

If missed. Register anyway, immediately. HMRC sends late registrants a letter or email with a filing deadline of 3 months from its date — but the payment deadline stays 31 January 2027, so every week of delay compresses the time you have to work out and pay the bill (gov.uk: deadlines).

What to do now. If 2025-26 was your first year over the line, register this week — the UTR and activation steps take time you'd rather not spend in January.

31 October 2026 — paper Self Assessment returns

What it is. HMRC must receive your paper tax return for 2025-26 by 11:59pm on 31 October 2026 (gov.uk: deadlines). Receive, not postmark — allow for the post.

Who it applies to. Only people filing on paper. Most people file online and get three more months.

If missed. A late return means an initial £100 penalty; after 3 months, £10 per day up to £900; after 6 and again at 12 months, a further 5% of the tax due or £300, whichever is greater (gov.uk: penalties). But note: an online return submitted by 31 January 2027 is on time — if you're up against the paper deadline, switching to online filing is usually the calmer route.

What to do now. If you file on paper, post it early. If you were only doing paper out of habit, set up online filing instead and buy yourself until January.

7 November 2026 — the MTD quarterly update (the big one)

What it is. The second Making Tax Digital for Income Tax quarterly update of 2026-27, due by 7 November 2026. It's cumulative — gov.uk: "Each time you send a quarterly update it will cover from the start of the tax year to the end of the update period, not just the previous three months" — so this one covers 6 April to 5 October 2026, or 1 April to 30 September 2026 if you elected calendar update periods; the deadline is 7 November either way (gov.uk: send quarterly updates). Nothing is payable on the day — payment dates are unchanged at 31 January, and 31 July where payments on account apply (gov.uk: deadlines).

Who it applies to. Sole traders and landlords mandated into MTD from 6 April 2026 — broadly, those whose combined gross self-employment and property income was over £50,000 in 2024-25. The cumulative design also means any mistake in your August submission is fixed simply by correcting your records: the November update covers the same ground again and supersedes it.

If missed. For the 2026-27 tax year, HMRC has confirmed there are no penalties for missing a quarterly update deadline. From later tax years, each miss earns a penalty point; at 4 points there's a £200 penalty, and £200 for each further miss at the threshold, with points expiring after 24 months if you stay below it (gov.uk: MTD penalties). No penalty isn't the same as no consequence, though — falling behind now just moves the catch-up into January.

What to do now. Get your records complete to 5 October and reconciled before you submit. The full walkthrough — periods, spreadsheets and bridging software, the readiness checklist — is in our 7 November deadline answer.

30 December 2026 — file online if you want the bill taken through your tax code

What it is. Submit your online return by 11:59pm on 30 December 2026 (not the 31st) if you want your Self Assessment bill collected through your PAYE tax code across the following year, instead of as a lump sum (gov.uk: deadlines).

Who it applies to. All three conditions must hold: you owe less than £3,000, you already pay tax through PAYE (you're an employee or get a company pension), and you filed by the deadline — paper by 31 October, or online by 30 December (gov.uk: pay through your tax code). That's a lot of side-hustlers with day jobs. HMRC sets it up automatically when you qualify, unless you ask them not to on the return.

If missed. No penalty — you simply lose the option. Your return is still on time until 31 January 2027; you'll just pay the bill as a lump sum by then instead of spreading it interest-free through your 2027-28 pay.

What to do now. If you're employed with a small side-hustle bill, treat 30 December as your real filing deadline, not 31 January.

31 December 2026 — the platforms' reporting year closes (online sellers)

What it is. Vinted, eBay, Depop, Etsy, Airbnb and other digital platforms collect seller information per calendar year and send it to HMRC by the following January — gov.uk's own example: "information collected about you between 1 January 2024 to 31 December 2024 will be reported to HMRC by 31 January 2025" (gov.uk: selling on a digital platform). So 31 December 2026 closes the year that gets reported by 31 January 2027.

Who it applies to. Sellers who pass roughly 30 sales or €2,000 (about £1,700) on a platform in the calendar year — platforms don't report you below those levels (gov.uk). Being reported is an information rule, not a tax bill — whether you owe tax still depends on whether you were trading and whether you passed the £1,000 trading allowance in the tax year. That distinction, and what to do if HMRC writes to you, is our Vinted/eBay HMRC letter answer.

If missed. There's nothing to miss — no action is due from you on 31 December. It's a reporting cutoff to be aware of, not a deadline.

What to do now. Know your two running totals — calendar-year sales per platform, and tax-year trading income across all platforms — so a platform email in the new year is information, not a fright.

Landlords: nothing new is dated in this window

We checked, so you don't have to. The Renters' Rights Act's main tenancy reforms commenced on 1 May 2026, and the latest commencement regulations (Commencement No. 2, SI 2026/421) set no new commencement dates between September and December 2026. Later phases — the PRS database, the ombudsman — remain undated as at 26 August 2026. What's already in force, with honest IN FORCE / DATED / DATE TBC labels, is in our landlord checklist. Landlords in Self Assessment, of course, still face the 5 October, 31 October and (if in MTD) 7 November dates above.

The horizon: 31 January 2027

Just past this window sits the one everyone knows: 11:59pm on 31 January 2027 — online filing for 2025-26 and payment of any tax due, plus the first 2026-27 payment on account if payments on account apply to you (gov.uk: deadlines). Late payment adds 5% of the unpaid tax at 30 days, 6 months and 12 months, plus interest (gov.uk: penalties). Everything on this page is, one way or another, about making that date boring.

Quick answers

Is there anything to pay between September and December 2026?

For most Self Assessment taxpayers, no — payment dates are 31 January and, where payments on account apply, 31 July (gov.uk). VAT-registered businesses pay with each quarterly return as usual.

I missed 5 October — is it a disaster?

No, but move fast. Register now; HMRC gives late registrants 3 months from their letter to file, and payment is still due 31 January 2027 (gov.uk).

Does 31 October matter if I file online?

No. The paper deadline only applies to paper returns; online returns are on time until 11:59pm on 31 January 2027.

Is 30 December a real deadline or a myth?

Real, and it's the 30th, not the 31st — it's the online filing cutoff for having a bill under £3,000 collected through your PAYE tax code (gov.uk).

Do landlords have new Renters' Rights duties starting this autumn?

Nothing newly dated in this window. The main reforms commenced 1 May 2026; the latest commencement regulations set no September–December 2026 dates (SI 2026/421).