If you owe a student loan and you file a Self Assessment return, HMRC collects your repayment through that return rather than leaving it to an employer. The repayment is worked out from your income for the whole tax year, added to your bill, and due on the same day as your tax. This guide explains who repays this way, what the thresholds and rates are, how the section of the return works and when the money is due.
When Self Assessment collects your student loan
Most employees repay through PAYE, with the employer deducting a slice of each payslip. Self Assessment takes over, or tops up, when you have income that is not taxed through a payroll. gov.uk says that if you are self-employed you make repayments through Self Assessment when you complete your tax return. The same applies if you file a return for another reason, such as rental income or untaxed dividends.
Two points often cause confusion:
- You can be in both systems at once. If you are employed and also self-employed, your employer keeps deducting through PAYE. At the end of the year the return looks at your combined income and deducts what PAYE already took from the amount you owe.
- Off-payroll working. gov.uk says that if the off-payroll working rules (IR35) apply to you, you must make your repayments through Self Assessment.
The rules sit in the Education (Student Loans) (Repayment) Regulations 2009. Regulation 28 says repayments for people who must file a return are made, accounted for and recovered in the same manner as income tax. Postgraduate Loan borrowers have been able to repay through Self Assessment since April 2020, according to HMRC's Collection of Student Loans manual.
Thresholds and rates
You repay a percentage of income above a threshold that depends on your plan. gov.uk gives the rates as:
- 9% of income over the threshold for Plan 1, 2, 4 and 5;
- 6% of income over the threshold for a Postgraduate Loan.
The thresholds are set each tax year, and the year matters. These are the annual figures, with the sources checked on 11 October 2026.
| Loan | 2025/26 threshold | 2026/27 threshold |
|---|---|---|
| Plan 1 | £26,065 | £26,900 |
| Plan 2 | £28,470 | £29,385 |
| Plan 4 | £32,745 | £33,795 |
| Plan 5 | No repayments before April 2026 | £25,000 |
| Postgraduate Loan | £21,000 | £21,000 |
The 2025/26 column comes from gov.uk's rates and thresholds for employers 2025 to 2026 page and the 2025 to 2026 student loan terms and conditions. The 2026/27 column comes from the 2026 to 2027 terms and conditions and gov.uk's student loan and postgraduate loan guidance for employers. Schedule 1A of the 2009 Regulations on legislation.gov.uk fixes the Postgraduate Loan at £21,000 and the Plan 5 threshold at £25,000 for 2026/27.
The 2025/26 return, which is due by 31 January 2027, uses the 2025/26 column. gov.uk's how much you repay page shows the current figures and is the place to check if the thresholds change again.
Which plan am I on?
Your plan is decided by when and where you started your course, not by how you repay. gov.uk's terms and conditions guide and HMRC's SA150 notes describe them as follows:
- Plan 1: courses started before 1 September 2012.
- Plan 2: courses started between 1 September 2012 and 31 July 2023.
- Plan 4: the Scottish plan, for Scottish students who started an undergraduate or postgraduate course on or after 1 September 1998.
- Plan 5: courses started on or after 1 August 2023.
- Postgraduate Loan: a Master's from 1 August 2016, or a Doctoral loan from 1 August 2018.
Moving from PAYE to Self Assessment does not change your plan. Only the collection route changes. The Student Loans Company can confirm your plan, and the online return asks for it. If you have more than one kind of loan you repay them at the same time, each against its own threshold.
What counts as income
The calculation uses your total Self Assessment income, not just your profit from self-employment. gov.uk says the income counted includes:
- PAYE employment income, with all employments combined, even where one is under the threshold;
- self-employed profits;
- property income;
- unearned income, but only if the total exceeds £2,000.
This is why a person with a modest salary and a side business can find a larger repayment than their payslips suggested. For self-employed income, the profit figure comes from the self-employment page SA103. For the rest of the return, see the SA100 overview.
How the return collects it
The student loan section of the SA100 is headed "Student and Postgraduate Loan repayment". You complete it if the Student Loans Company says your repayments were due to start on or before 6 April of the tax year you are reporting. gov.uk says this applies even if your income was below the threshold, or an employer already took repayments. If you repay both a student loan and a Postgraduate Loan, you complete both parts.
The section asks for:
- whether your repayments began before 6 April of the tax year, based on the letter from the Student Loans Company;
- the total student loan repayments your employers deducted, from your P60 and payslips;
- the total Postgraduate Loan repayments your employers deducted, from the same documents.
HMRC does the rest. It applies the 9% or 6% to your whole-year income above your threshold, then subtracts the amounts PAYE already took. The result is added to your Self Assessment bill. Check the box numbers on the current year's form and in HMRC's SA150 notes, because the layout can move between years.
A worked example
Suppose in 2025/26 you are on Plan 2 and your total Self Assessment income, before any PAYE offset, is £45,000.
| Step | Working | Result |
|---|---|---|
| Income above the Plan 2 threshold | £45,000 minus £28,470 | £16,530 |
| Repayment at 9% | 9% of £16,530 | £1,487.70 |
If you also hold a Postgraduate Loan, add a second calculation against its own threshold: £45,000 minus £21,000 is £24,000, and 6% of that is £1,440. The two loans together would come to £2,927.70. If your employer had already deducted, say, £900 of that through PAYE, only the remaining amount is added to your Self Assessment bill. The figures are illustrative; the real calculation is HMRC's and uses your exact income.
When it is due
HMRC treats the repayment as income tax. Regulation 35 of the 2009 Regulations says it must be paid on or before 31 January following the end of the tax year, with a later date only where HMRC issued its notice to file late, in line with section 59B of the Taxes Management Act 1970. In practice, for the 2025/26 return that is 31 January 2027, the same day as your online return and balancing payment. See the Self Assessment deadlines guide for the full calendar.
gov.uk's payments on account page lists student loan repayments for self-employed people as part of the balancing payment. If you are budgeting for January, include the loan alongside your income tax and Class 4 National Insurance. Our payments on account guide explains how the advance payments work and why a large balancing payment arrives alongside the first instalment.
Mistakes to avoid
- Assuming PAYE settled it. Your employer's deductions are only part of the answer. The return recalculates on your combined income.
- Skipping the section because your income was low. If the Student Loans Company says repayments had started, gov.uk says you complete the section even when you are under the threshold.
- Making voluntary payments and expecting them to count. gov.uk's guidance says voluntary payments are separate from employer or tax return collections and cannot be refunded.
- Forgetting the overseas rules. gov.uk says that if you leave the UK for more than 3 months you must tell the Student Loans Company, and you will generally keep repaying.
How ac-co helps
ac-co drafts your SA100 from your connected bank, books and HMRC's own data, so the income that drives your student loan repayment is already on the page. It shows the full tax computation, including the repayment line, and files only after you approve it. ac-co does not decide which plan you are on; confirm that with the Student Loans Company and check the figures against gov.uk before you file.