Q4 2026 Key Dates for UK Small Businesses

By Tamsin Elden, COO at Cubefunder. Published 22nd October 2026.

Key takeaway: UK small businesses have nine key dates to plan for before the end of 2026. They include the Autumn Budget (28th October), the paper Self Assessment deadline (31st October), VAT and MTD deadlines (7th November), Black Friday (27th November), Cyber Monday (30th November), Small Business Saturday (5th December), the Christmas bank holidays (25 and 28th December) and New Year’s Eve (31st December).

Q4 is busy enough without a missed deadline. Between tax returns, the biggest trading weekends of the year and the Christmas shutdown, a lot can land on a small business at once.

We’ve pulled together the key dates for UK small businesses from now until the end of December 2026. Each one comes with a quick to-do, so you can plan your cash flow, your staff and your stock before the year is out. Save this page so it’s there when you need it.

What are the key dates for UK small businesses in Q4 2026?

Here are the nine dates to put in the diary, from the Autumn Budget in October to New Year’s Eve.

What’s happening in October 2026?

Wednesday 28th October: Autumn Budget 2026

The Government will set out its tax and spending plans in the Autumn Budget on Wednesday 28th October 2026. Changes to business taxes, reliefs and investment incentives could affect your costs next year.

Your to-do: speak to your accountant after the announcement to see how any changes affect your business. Hold off on big decisions that depend on tax treatment until you know what’s changed.

Saturday 31st October: paper Self Assessment deadline

HMRC must receive paper Self Assessment tax returns for the 2025/26 tax year by midnight on Saturday 31st October 2026. As it’s a Saturday, post yours early. If you file online, you have until 31st January 2027 (GOV.UK).

Your to-do: not posted yet? Switch to online filing and avoid the £100 late-filing penalty. You’ll need to register for HMRC online services first, and HMRC posts you an activation code, so don’t leave it until January.

What’s happening in November 2026?

Saturday 7th November: VAT and MTD deadline day

VAT returns and payments are due by Saturday 7th November 2026 for VAT quarters ending 30th September. If you’re on Making Tax Digital for Income Tax, your quarterly update for the period to 5th October is due on the same day.

Because the deadline falls on a weekend, the money must reach HMRC by Friday 6th November, unless you pay by Faster Payments (GOV.UK). Paying late costs money: HMRC charges late payment interest from the first day overdue, and late payment penalties from day 16 (GOV.UK).

Making Tax Digital (MTD) for Income Tax is HMRC’s system that requires some sole traders and landlords to keep digital records and send quarterly updates through compatible software. It doesn’t apply to limited companies.

Your to-do: it’s a weekend, so unless you pay by Faster Payments, make sure the money reaches HMRC by Friday 6th November. If cash is tight, read our guide to using a business loan to pay VAT, which also covers HMRC’s Time to Pay plan.

Friday 27th November: Black Friday

Black Friday is one of the biggest shopping events of the year. Stock, staffing and advertising costs often land weeks before the extra sales come in, which can squeeze cash flow just as the busiest period starts.

Your to-do: plan your November cash flow now, so you can buy stock ahead of the rush. Remember that bigger sales now mean a bigger VAT bill next quarter.

Monday 30th November: Cyber Monday

Cyber Monday is a major day for online retailers to drive digital sales. Make sure your website, stock and delivery processes can handle the extra orders.

Your to-do: test your checkout on mobile, check your stock levels and let customers know your delivery cut-off dates.

What’s happening in December 2026?

Saturday 5th December: Small Business Saturday UK

Small Business Saturday UK is a nationwide day celebrating independent businesses, with customers actively looking to shop local. In 2026 it falls on Saturday 5th December.

Your to-do: share your story with #SmallBizSatUK and give your regulars a reason to come in that day.

25th - 28th December: Christmas and bank holidays

Christmas Day is Friday 25th December 2026. Boxing Day falls on a Saturday, so the bank holiday moves to Monday 28th December in England and Wales (GOV.UK). For most businesses, that means a four-day break, back to work on Tuesday 29th December.

Banks don’t process most payments on bank holidays, so anything due over the break, such as wages, rent or supplier invoices, may need to go out earlier.

Your to-do: let staff, suppliers and customers know your closing days and last order dates.

Thursday 31st December: New Year’s Eve

New Year’s Eve is the final day of 2026, and a good time to review business performance, check your cash flow and set financial priorities for the year ahead. New Year’s Day, Friday 1st January 2027, is a bank holiday.

Your to-do: review your Q4 figures and set your financial goals for the first quarter of 2027.

Which other deadlines should you check?

Some important deadlines depend on your own business, not the calendar. If you run a limited company, check:

• Corporation Tax payment: usually due 9 months and 1 day after the end of your accounting period.
• Companies House annual accounts: usually due 9 months after your company’s financial year end.
• Confirmation statement: due at least once every 12 months.
• Other VAT stagger groups: if your VAT quarter ends in October or November, your deadlines fall on 7th December 2026 and 7th January 2027.

Your accountant or your HMRC and Companies House online accounts will show the exact dates for your business.

Frequently asked questions

Is your business ready for 2027?

From managing cash flow through the Christmas rush to preparing for new opportunities in the new year, a little planning now goes a long way. If you need funding for stock, a tax bill or growth, Cubefunder offers short-term business loans from £5,000 to £100,000 for limited companies in England and Wales, with fixed daily or weekly repayments. Borrowing isn’t right for every business, so compare your options and make sure repayments are affordable.

See how our process works, then check your eligibility. It takes under a minute and won’t affect your credit score.

This article is general guidance only. Check the dates that apply to your business, and speak to your accountant about your circumstances. Cubefunder is a trading name of Tallaght Financial Ltd (company number 09261403). Tallaght Financial Ltd is authorised and regulated by the Financial Conduct Authority (FRN 786297). Loans to limited companies are not regulated by the FCA. All lending is subject to status.