When payments on account are triggered
Payments on account are HMRC's way of collecting your tax bill in advance across the year rather than in one January lump. They're the single biggest surprise for freelancers filing their first meaningful Self Assessment — the January bill can end up 50% larger than expected because you're paying next year's tax at the same time. This guide explains the mechanic, when they apply, and how to plan for them.
When payments on account are triggered
You owe payments on account if: 1. Your Self Assessment tax bill exceeds £1,000, AND 2. Less than 80% of the tax you owe is deducted at source (through PAYE, for example).
Most self-employed freelancers meet both. The first payment on account applies from the second year of significant Self Assessment liability.
The two-payment structure
Each payment on account is 50% of the previous year's tax bill.
For a 2024/25 tax bill of £6,000: - 31 January 2026: balancing payment for 2024/25 (any amount not yet paid) + payment on account 1 for 2025/26 (£3,000). - 31 July 2026: payment on account 2 for 2025/26 (£3,000). - 31 January 2027: balancing payment for 2025/26 (difference between actual 2025/26 tax and the £6,000 already paid) + payment on account 1 for 2026/27.
It's rolling. Once you're in the system, each January you're paying the balancing amount for the completed year plus 50% of that year's tax as advance for the current year.
Planning for the first-year shock
First-year Self Assessment freelancer with £8,000 tax bill: they'll owe £8,000 balancing + £4,000 payment on account = £12,000 payable 31 January. This is often 50% more than expected.
Mitigation options: (1) reduce payments on account by SA claim if you know next year's income will be lower, (2) set up a tax savings account and deposit 25-30% of every invoice automatically, (3) request Time to Pay if cash-tight, (4) work with an accountant to project the January bill accurately.
Worked example
Ravi filed his first Self Assessment for 2024/25 in January 2026. Tax + Class 4 NI came to £5,400. Because it exceeded £1,000, he owes payments on account for 2025/26. 31 January 2026: pay £5,400 (2024/25 balancing) + £2,700 (POA 1 for 2025/26) = £8,100. 31 July 2026: pay £2,700 (POA 2 for 2025/26). End of 2025/26: if actual tax is £6,000, he's already paid £5,400 in POAs; balancing payment £600 on 31 January 2027, plus first POA for 2026/27 of £3,000 = £3,600 total. Critical: he needs to set aside for the balancing amount + the next POA every January, not just the previous year's tax.
Reference table
| Date | What's due | Example (2024/25 tax £6,000) |
|---|---|---|
| 31 January 2026 | 2024/25 balancing + 2025/26 POA 1 | £6,000 + £3,000 = £9,000 |
| 31 July 2026 | 2025/26 POA 2 | £3,000 |
| 31 January 2027 | 2025/26 balancing + 2026/27 POA 1 | Depends on 2025/26 actual |
| Reduction claim | If income will be lower | File SA303 to reduce POA |
| Overpayment | If actual tax lower than POAs | Refunded after next SA filed |
POA cash-flow checklist
- Set aside 25-30% of each invoice into a tax savings account
- Add another slice (5-10%) if this is a first-year POA situation
- Diary 31 January and 31 July POA dates on repeat
- Model POA into your annual cash-flow forecast
- If income will drop: file a claim to reduce POA (SA303)
- If cash-tight before deadline: request Time to Pay proactively
Yes, if you have reason to believe next year's tax will be lower. File a claim (SA303) explaining why. HMRC accepts reasonable estimates. If your actual tax is higher than the reduced amount, interest is charged on the shortfall.
You still pay POAs based on last year's bill. The balancing payment the following January covers the shortfall. No penalty for the shortfall provided you pay the balancing amount on time.
No — they don't earn interest for you. HMRC just holds them against your future tax. Interest goes the other way: on unpaid or late amounts.
You reclaim the POAs already paid as an overpayment on the following January's return. You get a refund. In the meantime, your cash is tied up with HMRC.
Yes — PAYE-deducted tax reduces the amount considered 'not at source', which can eliminate POAs even if your total tax bill exceeds £1,000.
Sources & official references
Related on FreelanceToolkit UK
This guide is general information based on UK rules for the 2025/26 tax year. It is not personal tax or legal advice. For decisions affecting your tax position or legal exposure, consult a qualified accountant or solicitor.