Estimate your monthly student loan repayment based on your income, see how your balance changes over time, and find out if it could be written off.
Thresholds and rates as of 2025/26 (example — check your repayment plan)
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This UK student loan calculator estimates your monthly repayment based on your income, the repayment threshold for your loan plan, and the repayment rate — then projects how your outstanding balance changes over time as interest accrues and repayments are made, including whether the loan might be written off before it's fully repaid.
Unlike a conventional loan, your monthly repayment isn't based on your balance or interest rate — it's a fixed percentage of your income above a threshold, regardless of how much you owe. Meanwhile, interest accrues on your outstanding balance each year. If your repayments are less than the interest accrued, your balance can grow over time, even while you make every payment — until either the balance is cleared or the write-off period is reached, whichever comes first.
Formula: Annual Repayment = max(0, Income − Repayment Threshold) × Repayment Rate. Each year: Interest = Balance × Interest Rate. If Balance + Interest ≤ Annual Repayment, the loan is cleared. Otherwise, Balance = Balance + Interest − Annual Repayment, and this repeats until the write-off year.
Example: With a £30,000 income, a £27,295 repayment threshold (example — check your plan), and a 9% repayment rate, the income above the threshold is £2,705, giving an annual repayment of about £243 (roughly £20/month). On a £45,000 balance at 7.3% interest (example rate — check your plan), the interest accrued each year (about £3,285) is far more than the repayment, so the balance grows over time — after 30 years, a substantial balance would likely remain and be written off. (Note: this example assumes constant income and doesn't account for future income growth, which would increase repayments over time — figures are for illustration only.)
UK student loans are repaid through the tax system, as a deduction alongside Income Tax and National Insurance, calculated as a percentage of income above a threshold that depends on your loan plan (Plan 1, Plan 2, Plan 4, Plan 5, or Postgraduate, depending on when and where you studied). Because repayments depend only on income — not on how much you borrowed or the interest rate — many borrowers, especially those on lower or middle incomes, never repay their loan in full before it's written off (typically 25-40 years after starting repayment, depending on the plan), at which point any remaining balance is cancelled. This is why student loans are often described as functioning more like an additional income-based tax than a conventional loan — the headline "amount borrowed" or "interest rate" matters less for many borrowers than their income over their working life. If you're considering whether extra voluntary repayments make sense, this depends heavily on whether you're likely to repay the loan in full before write-off — for many borrowers on lower incomes, voluntary overpayments may not reduce what they ultimately pay.
Your repayment is a fixed percentage (9% for most undergraduate plans, 6% for postgraduate loans) of your income above your plan's repayment threshold — not based on your loan balance or the interest rate. It's deducted automatically through PAYE if you're employed, similar to Income Tax and National Insurance.
Interest accrues on your balance regardless of your repayments. If the interest added in a year is more than your annual repayment (which depends only on your income, not your balance), your balance increases. This is common for borrowers with lower incomes relative to their balance, and the loan may be written off before it's fully repaid.
Any remaining balance is cancelled, and you stop making repayments. The write-off period depends on your loan plan (commonly 25, 30, or 40 years after the April you became eligible to repay, depending on the plan) — check your specific plan's rules.
It depends on whether you're likely to repay your loan in full before write-off. If you're on track to be written off with a remaining balance, voluntary overpayments may not reduce your total cost — they'd effectively be "lost" at write-off. If you're likely to repay in full (e.g., on a high income relative to your balance), overpayments could reduce the total interest paid.
This depends on when and where you started your course — broadly, Plan 1 covers many pre-2012 English and Welsh students (and most Scottish and Northern Irish students), Plan 2 covers most English and Welsh students starting between 2012-2023, Plan 5 covers those starting from August 2023 onwards, Plan 4 applies to Scottish students under newer arrangements, and Postgraduate Loans cover Master's and Doctoral loans. Check your account on the official student loans repayment service to confirm your plan.
No. UK student loans don't appear on standard credit reference agency files and don't affect your credit score, though the repayment deduction does reduce your take-home pay, which lenders may consider when assessing affordability for other borrowing (such as a mortgage).
Disclaimer: The information, rates, and thresholds provided on this page are for educational and illustrative purposes only and do not constitute financial advice. Student loan repayment thresholds, interest rates, repayment rates, and write-off periods vary by plan (Plan 1, 2, 4, 5, or Postgraduate) and are reviewed periodically by the government. This calculator assumes constant income and does not account for future income changes, which significantly affect actual repayments and total amounts repaid. Always check your specific plan details via the official student loans repayment service and consult a qualified financial adviser if needed.