Student Loan Plan Checker
Our student loan plan calculator models how your student loan balance evolves over time based on your starting balance, interest rate, salary growth assumptions, and repayment plan. It shows whether you are likely to repay in full before write-off, or whether a portion of your balance will be cancelled — a crucial distinction that determines whether voluntary overpayments are ever worth making.
Student Loan Plan Calculator
Compare all UK student loan plans side by side. See your monthly repayments, total interest, whether you'll clear your balance, and if writing off makes financial sense — based on 2026/27 thresholds.
How Student Loan Interest Works
Interest accumulation depends on your plan. Plan 1 loans accrue interest at the lower of RPI inflation or the Bank of England base rate plus 1%. Plan 2 loans charge RPI plus up to 3% while studying, then a sliding scale from RPI to RPI+3% depending on income once repaying. Plan 5 loans accrue interest at RPI throughout. The Postgraduate Loan charges RPI plus 3% at all times.
For many Plan 2 borrowers, the interest rate often exceeds the effective repayment rate. This means the outstanding balance can grow faster than it is repaid in the early career years, only beginning to fall as salary rises. This is exactly why the 30-year write-off mechanism exists — the system is designed for many graduates never to fully repay.
When Overpaying Makes Sense
Overpaying is only financially rational if you are certain to repay the loan in full before write-off regardless. If your projections show the balance clearing at year 25 on standard repayments, overpaying to clear it at year 20 saves five years of interest — potentially a meaningful sum. But if you are projected to still carry a large balance at year 30 when it is written off, every voluntary overpayment is money you would never have repaid anyway.
Use this calculator to model both scenarios and compare the projected total repaid under standard repayments versus voluntary overpayments. For most Plan 2 graduates, particularly those in lower to middle-income careers, standard repayments and no overpayment is the optimal strategy.
Frequently Asked Questions
Yes. The Plan 2 threshold of £29,385 is frozen until April 2030 as confirmed in the 2025 Budget. This means more of your earnings fall within the repayment band each year as salaries rise with inflation — increasing effective repayment rates over the freeze period.
Plan 5 applies to new English and Welsh students starting from August 2023. The threshold is lower (£25,000 vs £29,385), the write-off period is longer (40 vs 30 years), and interest accrues at RPI rather than RPI+3%. Plan 5 is generally less favourable for lower earners due to the lower threshold but more favourable for higher earners due to RPI-only interest.
No — your repayment plan is determined by when and where you studied. It cannot be changed. However, if you have both an undergraduate and postgraduate loan, each follows its own plan rules simultaneously.
Higher salary growth means faster repayment but also higher income — pushing you further above the threshold each year. Use this calculator with different salary growth assumptions (2%, 3%, 5%) to see the range of outcomes. Use our Income Tax Calculator to model how salary growth affects your overall tax position.
In any year where your earnings fall below your plan threshold, no repayments are due and the clock still ticks toward write-off. Career breaks, maternity leave, or part-time working do not pause the write-off timer. Our Maternity Pay Calculator shows statutory maternity pay levels during a career break.
Enter your salary, outstanding balance, and current interest rate. Then select the number of years since graduation. The calculator models your repayment trajectory, showing the balance each year and whether you are on track to clear the loan before write-off. For Plan 2 borrowers, the interest rate can exceed the repayment rate at lower incomes, causing the balance to grow even while you repay — this is particularly relevant for those who graduated with large postgraduate debts. The question of whether to overpay voluntarily is complex. For Plan 2, voluntary overpayments only save money if you are genuinely on track to repay in full before the 30-year write-off. If you are not — which applies to the majority of Plan 2 graduates — voluntary overpayments simply reduce a balance that would be written off anyway.
Important Information
This calculator is provided for general information and planning purposes only. It does not constitute financial or tax advice and should not be relied upon as such. Figures are indicative estimates based on simplified, publicly available criteria and stated assumptions. Actual results depend on your full circumstances. See our Disclaimer for further information.