- Sole trader: the Self Assessment return and balancing payment by 31 January, plus payments on account on 31 January and 31 July, which catch people out in their second year
- Limited company: Corporation Tax paid 9 months and 1 day after the year end for most companies, the CT600 return within 12 months, accounts to Companies House within 9 months, and a confirmation statement within 14 days of its review date
- VAT once you cross the registration threshold: each quarterly return and payment is due 1 month and 7 days after the quarter ends
- Payroll, including yourself on a company payroll: PAYE and National Insurance by the 22nd of the following month if you pay electronically, or the 19th by post
- Class 4 National Insurance if you are self-employed, at 6% on profits between £12,570 and £50,270 and 2% above, on top of income tax (As of Oct 2026)
Monthly, 22nd: PAYE and National Insurance for both of you.
Quarterly: VAT return and payment, one month and seven days after each quarter end.
31 December: statutory accounts to Companies House, nine months after your March year end.
1 January: Corporation Tax, nine months and one day after your March year end.
Within 14 days of its review date: confirmation statement, which is not tax and is not tied to your year end.
31 January: your personal Self Assessment, for dividends.
31 March: your Corporation Tax return (CT600), 12 months after your year end.
The one people miss is the confirmation statement, because its date has nothing to do with the others. A missing one starts the route to the company being struck off.
Want this as a calendar you can put in your phone?
Two of the seven are not tax at all, and those are the ones that catch people.
Payments on account
HMRC collects next year's tax in advance: two payments on account, each half of last year's bill, due 31 January and 31 July. They do not apply if last year's bill was under £1,000, or if more than 80% of it was taxed at source. As of Oct 2026.
Taxes Management Act 1970 ss.59A and 59B; Income Tax (Payments on Account) Regulations 1996 reg 3
| Income tax: (£40,000 minus £12,570) x 20% | £5,486 |
| Class 4 National Insurance: £27,430 x 6% | £1,645.80 |
| First payment on account for 2026/27, half the bill | £3,565.90 |
| Due on 31 January 2027 | £10,697.70 |
| Then due on 31 July 2027 | £3,565.90 |
The second payment on account. January takes 26.7% of a year's profit in one go, which is why the second year hurts.
Making Tax Digital for Income Tax
Sole traders and landlords whose qualifying income was over £50,000 on their 2024 to 2025 return have used it since 6 April 2026. Over £30,000 on the 2025 to 2026 return brings you in from 6 April 2027, and over £20,000 on the 2026 to 2027 return from 6 April 2028. Qualifying income is gross trading and property income, not profit. Quarterly updates are due 7 August, 7 November, 7 February and 7 May. As of Sep 2026.
HMRC guidance: Use Making Tax Digital for Income Tax; Penalties for Making Tax Digital for Income Tax
What lateness costs
For the 2025 to 2026 return due 31 January 2027, a late return costs £100 at once, then £10 a day after 3 months, up to £900, and late tax costs 5% at 30 days, 6 months and 12 months. In Making Tax Digital since April 2026, your 2026 to 2027 return earns a penalty point instead (£200 at 4 points), and late tax costs nothing if paid or put on a plan within 30 days, otherwise 3% at day 15, 3% more at day 30 and 10% a year from day 31. From the 2027 to 2028 return every personal return moves to points (£200 at 2 points outside Making Tax Digital). Interest runs on top at Bank Rate plus 4%, 7.75% since 9 January 2026. Late private company accounts cost £150 to £1,500, doubled if late two years running. As of Sep 2026.
GOV.UK Self Assessment penalties; HMRC guidance: Penalties for Making Tax Digital for Income Tax; HMRC interest rates for late payments; Companies Act 2006 s.453
The amount is the same either way. Only one version involves a panic.
Budget 2026 was on 28 October 2026. Its changes mostly start in 2027, and Greymill's figures were rechecked against it; ask MARCUS what changes for you.
I run a [type of business] in [England, Scotland, Wales or Northern Ireland], set up as a [sole trader or limited company] with a year end of [date], turning over roughly [amount] a year. I [am or am not] VAT registered and I [do or do not] run a payroll. Give me a calendar of what is due and when over the next twelve months, and how much to set aside from each payment.
Every lesson ends with a question to hand to a Greymill specialist, who answers with what it knows about your business.
More in Cash, tax and getting paid
- Where the money actually goesBusy, profitable on paper, and the account never grows.Read the lesson
- When a customer will not payThere is an order to this, and skipping to the end costs you money.Read the lesson
- When a customer will not payThere is an order to this, and skipping to the end costs you money.Read the lesson
- Knowing what is due and whenFederal, state and quarterly. Nothing here is difficult, but the surprise is expensive.Read the lesson
- What you can and cannot claimMost people either claim nothing out of fear, or everything out of hope.Read the lesson
- When the books are months behindEveryone gets here. The way out is not to do it all in one weekend.Read the lesson