Student Loan Calculator UK
Estimate your student loan repayments based on income and repayment plan, and see how interest builds up over time.
Student loan details
How UK student loans work
UK student loans aren't like ordinary loans. You repay a percentage of income above a threshold, not a fixed monthly amount, and any balance left after the write-off period is cancelled. Interest is added while you study and repay, but what you actually pay back depends on your income, not the headline balance.
The calculator shows how the balance and interest build up over your course and repayment years. Which plan you're on (Plan 2, Plan 5 or postgraduate) sets the threshold and write-off period.
Key points about repayment
- You repay 9% of income above the threshold for undergraduate plans (6% for postgraduate loans).
- Repayments are collected through the tax system once you earn over the threshold.
- Any remaining balance is written off after the plan's set period.
- Because repayment is income-based, many graduates never repay the full balance – so overpaying voluntarily isn't always worthwhile.
Frequently asked questions – Student Loan Calculator UK
For undergraduate loans you repay 9% of everything you earn above the repayment threshold, collected through the tax system. If your income drops below the threshold, repayments stop. Postgraduate loans are 6% above their threshold.
Often not. Because repayment is a percentage of income and any balance is written off after the plan period, many graduates never repay the full amount. Overpaying only helps if you're a high earner likely to clear the whole balance before write-off.
Interest is added to the balance, but since you only ever repay based on income and the balance is eventually written off, the headline figure often matters less than it looks. The calculator shows how the balance grows so you can see the picture.