Key takeaways
- Sunday 31 January 2027: online Self Assessment returns for 2025 to 2026 are due, along with the balancing payment and the first payment on account for 2026 to 2027.
- Because 31 January is a Sunday, a Self Assessment payment must reach HMRC by Friday 29 January unless you pay by Faster Payments or card.
- Thursday 7 January: VAT returns and payments are due for quarters ended 30 November 2026.
- Tuesday 19 January: CIS monthly returns are due. Electronic PAYE payments are due by Friday 22 January.
- A late Self Assessment return gets an automatic £100 penalty, even if no tax is owed.
- From 1 January 2027 the main rate first-year allowance rises to 50%, and the unfair dismissal qualifying period falls to six months.
- Companies House accounts for 30 April 2026 year ends and Company Tax Returns for periods ended 31 January 2026 are due by 31 January.
The biggest UK deadline in January 2027 is Sunday 31 January, when 2025 to 2026 Self Assessment returns and payments are due. Before that come VAT on 7 January, CIS returns on the 19th and electronic PAYE on the 22nd. Several Budget 2026 measures also start on 1 January, so check client plans before the month begins.
January 2027 deadline calendar
| Date | Deadline and who it affects |
|---|---|
| Fri 1 Jan | New Year’s Day bank holiday |
| Fri 1 Jan | Corporation Tax due for periods ended 31 March 2026 |
| Fri 1 Jan | 50% first-year allowance and six month unfair dismissal rule start |
| Mon 4 Jan | Scotland bank holiday (2 January substitute day) |
| Thu 7 Jan | VAT return and payment for quarters ended 30 November |
| Thu 14 Jan | Quarterly instalments for large companies |
| Tue 19 Jan | CIS monthly return for 6 December to 5 January |
| Tue 19 Jan | PAYE cheques by post must reach HMRC |
| Fri 22 Jan | Electronic PAYE, NIC, CIS and student loan payments |
| Fri 29 Jan | Last working day for Self Assessment payments by slower methods |
| Sun 31 Jan | Self Assessment online returns and payments for 2025 to 2026 |
| Sun 31 Jan | Company Tax Returns for periods ended 31 January 2026 |
| Sun 31 Jan | Companies House accounts for 30 April 2026 year ends |
Self Assessment on 31 January
The online return for 2025 to 2026 must be filed by 11:59pm on 31 January 2027, according to GOV.UK’s deadlines page. The same date applies to the tax bill.
Two amounts are usually due:
- The balancing payment for 2025 to 2026.
- The first payment on account for 2026 to 2027. The second is due on 31 July 2027.
31 January 2027 is a Sunday. GOV.UK’s payment page says that when a deadline falls on a non-working day, the payment must reach HMRC on the last working day before, which is Friday 29 January. That rule does not apply to Faster Payments or debit or corporate credit card payments.
| Payment method | Time to reach HMRC |
|---|---|
| Faster Payments, CHAPS, card | Same or next day |
| Bacs, existing Direct Debit | 3 working days |
| New Direct Debit | 5 working days |
On our count, a Bacs payment should leave by Tuesday 26 January to reach HMRC by Friday 29 January.
Penalties if you miss it
The Self Assessment penalties are:
- £100 straight away if the return is late, even if no tax is due.
- £10 a day after 3 months, up to £900.
- 5% of the tax due or £300, whichever is greater, after 6 months and again after 12 months.
Late payment adds 5% of the unpaid tax at 30 days, 6 months and 12 months, plus interest. See HMRC late payment interest.
Use the Self Assessment checklist for 2027 to gather records. Returns for 2025 to 2026 also decide who must join Making Tax Digital in April 2027 under the £30,000 threshold.
VAT, PAYE and CIS
These are the routine monthly and quarterly dates.
- VAT, Thursday 7 January: returns and payments for quarters ended 30 November 2026. VAT deadlines do not move for weekends.
- CIS, Tuesday 19 January: monthly returns for the tax month 6 December to 5 January.
- PAYE, Friday 22 January: electronic payments for the same tax month. GOV.UK says cheques must reach HMRC by the 19th.
Making Tax Digital for Income Tax users have no January deadline. The update for the period to 5 January 2027 is due by 7 February 2027.
Corporation Tax and Companies House
Corporation Tax for companies with profits up to £1.5 million is due nine months and one day after the period end. For periods ended 31 March 2026 that is Friday 1 January, a bank holiday, so the payment must reach HMRC by Thursday 31 December unless you use Faster Payments.
- Company Tax Returns are due 12 months after the period end, so 31 January for periods ended 31 January 2026.
- Companies House accounts for private companies are due 9 months after the year end, so 31 January for 30 April 2026 year ends. Penalties start at £150.
- Large companies pay quarterly instalments on the 14th. For a year ended 31 December 2026, the third instalment is due on 14 January 2027. See Corporation Tax instalments.
What starts on 1 January 2027?
Budget 2026 and employment law changes take effect on New Year’s Day. The Budget’s overview of tax legislation lists these:
- Capital allowances: the main rate first-year allowance rises to 50% for spending on or after 1 January 2027 (paragraph 1.42).
- Bank surcharge: rises to 6% from 1 January 2027 to 31 March 2028 (paragraph 1.37).
- Fuel duty: the 5p cut is extended from 1 January to 30 June 2027 (paragraph 2.18).
- Unfair dismissal: employees can claim after six months’ service. See unfair dismissal after six months.
Other dates to diarise
- 18 January: ACCA December 2026 exam results.
- 20 January: HMRC consultations close on Corporation Tax administration and e-invoicing digital reporting.
- 28 January: Companies House incorporation statistics for October to December 2026.
What to do now
- Set a client cut-off for Self Assessment records in early January.
- Tell clients paying by Bacs to send money by 26 January.
- Check which clients owe a first payment on account for 2026 to 2027.
- Time capital spending around the 50% allowance on 1 January.
December’s dates are in deadlines for December 2026. The full year is in our tax calendar 2027.
Frequently asked questions
When is the Self Assessment deadline in January 2027?
Online returns and payments for 2025 to 2026 are due by 11:59pm on Sunday 31 January 2027.
Does the 31 January deadline move because it is a Sunday?
The filing deadline does not move. Payments by Bacs, Direct Debit or cheque must reach HMRC by Friday 29 January; Faster Payments and card payments can be made up to 31 January.
When is VAT due in January 2027?
For quarters ended 30 November 2026, the VAT return and payment are due by Thursday 7 January 2027.
When are PAYE payments due in January 2027?
Electronic payments are due by Friday 22 January. Cheques must reach HMRC by Tuesday 19 January.
What is the penalty for a late tax return in January 2027?
There is a £100 penalty straight away, then £10 a day after three months, up to £900.
Sources
Rates, thresholds and rules in this guide were checked against HMRC and GOV.UK guidance on 6 November 2026. Tax rules change, so check the current position on GOV.UK or with a qualified adviser before acting. This guide is general information, not personal advice.