Tax Deadlines Card 2025-26
Tax Deadlines Card 2025-26
Key Dates
| Deadline | Date |
|---|---|
| Register as self-employed | By 5 October after end of tax year you started |
| Self Assessment — online filing | 31 January |
| Self Assessment — paper filing | 31 October |
| SA balancing payment due | 31 January |
| SA payment on account 1 | 31 January |
| SA payment on account 2 | 31 July |
| P60 issued to employees | By 31 May |
| P11D filing (benefits in kind) | By 6 July |
| CIS monthly return | By 19th of each month |
| VAT returns | Every 3 months (quarterly) |
| Corporation tax payment | 9 months after accounting period end |
| CT600 filing | 12 months after accounting period end |
Penalties for Late Filing
| 1 day late (SA) | £100 automatic |
| 3 months late | £10/day for up to 90 days (max £900) |
| 6 months late | £300 or 5% of tax due (whichever is greater) |
| 12 months late | Further £300 or 5% of tax due |
Late filing = automatic penalties. Set calendar reminders. Late payment interest is charged from the due date — even if you have a payment plan.
SiteKiln provides general guidance only. This is not legal, tax, financial or professional advice. Always verify information and seek professional advice if unsure. © SiteKiln 2026
Related guides: