The best way to show how this works is with an example, HMRC require 50% on account in each January and July based on the tax paid for the year before.
If 5 April 2026 is your first year then you will not have made payments in January and July 2025 and so payment on 31 January 2027 in this example based on taxable profits of £25,000 will be:
| Tax and NIC Payments due | |||||
| Income Tax 2025/26 | £2,286.00 | ||||
| Class 4 NIC 2025/26 | £685.5 | ||||
| Total for 2015/26 | £2,971.80 | ||||
| Payment on account 31 January 2025 | 0 | ||||
| Payment on account 31 July 2025 | 0 | ||||
| Total paid on account | £0.00 | ||||
| Balancing payment due for 2025/26 | £2971.80 | ||||
| 1st Payment on account for 2026/27 | £1,485.90 | ||||
| Total payment due by 31 January 2027 | £4,457.70 | ||||
| 2nd Payment on account due by 31 July 2027 | £1,485.90 | ||||
If 5 April 2026 isn’t your first year and you made on account payments on January and July 2025 of £900 each then based on the same example the payments will be
| Tax and NIC Payments due | |||||
| Income Tax 2025/26 | £2,286.00 | ||||
| Class 4 NIC 2025/26 | £685.80 | ||||
| Total for 2025/26 | £2,971.80 | ||||
| Payment on account 31 January 2025 | £900.00 | ||||
| Payment on account 31 July 2025 | £900.00 | ||||
| Total paid on account | £1,800.00 | ||||
| Balancing payment due for 2025/26 | £1,171.80 | ||||
| 1st Payment on account for 2026/27 | £1,485.90 | ||||
| Total payment due by 31 January 2027 | £2,657.70 | ||||
| 2nd Payment on account due by 31 July 2027 | £1,485.90 | ||||
