How this is calculated
This calculator takes your current outstanding balance and projects it forward one year at a time, adding interest at the rate you enter and then subtracting the repayment your current income would generate, repeating until either the balance reaches zero or the plan's statutory write-off period is reached.
This is different from the student loan calculator elsewhere on this site, which only shows the next monthly or annual deduction. This one is aimed at the bigger question many graduates actually want answered: will I ever clear this, or will it be written off first.
Because both income and interest rates change over a working life, this is necessarily an approximation based on today's figures held constant, not a guaranteed forecast.
Why many loans are never fully repaid
For a large share of graduates, particularly on Plan 2 and Plan 5, annual interest added to the balance is close to or exceeds what is repaid at typical graduate salaries, meaning the balance can stay flat or even grow for years before falling. In practice many borrowers reach the statutory write-off point with some balance still outstanding, at which point it is cancelled entirely with no further liability.
This differs sharply from a commercial loan, where the borrower is expected to fully repay; a student loan behaves more like a graduate tax that stops once the write-off date is reached or the balance clears, whichever comes first.
Should you make voluntary overpayments?
Whether extra repayments make financial sense depends heavily on whether you are likely to clear the loan naturally before the write-off date. If projections suggest the loan would be written off with a balance still outstanding, voluntary overpayments effectively hand HMRC money that would otherwise have been cancelled.
If projections suggest you are on track to clear the loan comfortably before write-off, overpaying simply brings that date forward and reduces total interest paid, which is a more straightforward financial decision similar to overpaying any other debt.
What this means for your company
Treat the result as a planning figure for the 2026/27 tax year. If it changes what you were about to do, take a director's salary, a dividend, a large asset purchase or a filing decision, check it against your own accounts first. We can review the position with you and confirm the tax treatment before you commit.
Frequently asked questions
When is a student loan written off?
This depends on the plan: 25 years after becoming due to repay for Plan 1 and Plan 4, 30 years for Plan 2, and 40 years for Plan 5, measured from the April after you left or completed your course.
Does interest keep being added even if I am not repaying anything?
Yes, interest accrues on the outstanding balance regardless of whether your income is above or below the repayment threshold, so the balance can grow during periods of low or no income.
Should I overpay my student loan?
It depends on whether you are likely to clear the balance before the statutory write-off date. If you are not, overpaying may simply pay off a debt that would otherwise have been cancelled; if you are on track to clear it, overpaying saves interest.
Does this calculator use my actual interest rate?
It uses whatever rate you enter, which you should take from your latest Student Loans Company statement, since actual rates vary by plan, income band and the RPI figure published each year.