UK Student Loan 2026 — Plan 2 vs Plan 5 & Whether to Overpay

You borrowed £50,000 for university. You're now earning £45,000/year and repaying via Plan 2 Student Loan: 9% of income above £27,295. Your monthly payment is £156. You're wondering: should you overpay to clear it faster, or invest the extra money instead? The answer: probably not overpay. UK student loans are among the cheapest debt available (9% interest, but forgiven after 30 years). We'll walk through when overpayment makes sense and when it doesn't.

Plan 2 vs Plan 5: The Rules

For most of you: Plan 2 applies. Plan 5 is for older borrowers who took out pre-2012 loans.

Real-World Example: Loan Repayment Timeline

Meet Sarah, 26, with a £40,000 Plan 2 student loan. She's earning £40,000/year.

Plan 2 repayment:

• Income: £40,000
• Threshold: £27,295
• Amount above threshold: £12,705
• Repayment rate: 9% × £12,705 = £1,143.45/year = £95.29/month
• Interest accrual: £40,000 × (RPI+3%, say 6% = RPI if RPI is 3%) = £2,400/year

Year 1:

• Loan balance start: £40,000
• Interest accrued: £2,400
• Repayment: £1,143
• Loan balance end: £40,000 + £2,400 − £1,143 = £41,257 (loan growing)

Sarah's loan is growing because interest (£2,400) exceeds repayment (£1,143). She won't start reducing the balance until she earns enough to repay >£2,400/year.

Breakeven income (interest = repayment):

• £2,400 annual interest = 9% × (income − £27,295)
• £2,400 ÷ 0.09 = £26,667 income above threshold
• Breakeven income: £27,295 + £26,667 = £53,962/year

Sarah needs to earn >£54,000 for her loan to start shrinking.

Overpayment: Is It Worth It?

Sarah earns £40,000, obligated to repay £95/month. She has £200/month extra. Should she overpay the student loan?

Option A: Overpay £200/month (total £295/month)

• Loan balance: £41,257 (year 1 end, as above)
• Overpayment: £200 × 12 = £2,400/year
• Interest: still £2,400/year (growing)
• New balance: £41,257 + £2,400 − (£1,143 + £2,400) = £40,114
• Over 10 years: loan shrinking faster, but interest still ~£2,400/year
• To clear £40k at 6% interest with £2,400 overpayment + £1,143 minimum: ~8–9 years

Option B: Don't overpay, invest £200/month in ISA

• ISA grows at 5% real return (7.5% nominal)
• £200/month × 120 months (10 years) = £24,000 invested
• Growth at 7.5%: £24,000 × (1.075)^10 = £50,000 (approximately)
• Net wealth: £50,000

Option C: Overpay + Don't invest

• Student loan cleared in 8–9 years
• At year 9: loan is gone, but ISA is only £18,000 (9 years of growth)
• Net wealth: £0 debt (vs £18k assets in Option B)

Comparison:

• Option A (overpay): Debt cleared in 9 years, no extra assets
• Option B (invest): Debt exists 30 years (forgiven), but £50,000 in ISA by year 10

Option B is better because:

1. Student loan is cheap (6% effective interest after tax relief)
2. ISA returns are higher (7.5% nominal vs 6% real cost of student loan)
3. Student loan is forgiven in 30 years anyway (free money at the end)

The Tax Relief Twist

Wait—student loans aren't actually paid via income tax (no relief available). The 9% repayment comes straight from salary, but it's not an "expense" for income tax. So there's no tax relief.

But:

• ISA returns (in Option B) are tax-free (no CGT, no income tax on dividends)
• Student loan repayment is made from post-tax income (no deduction)
• This makes ISA investing even better (avoids all tax)

Higher Earner: When Overpayment Wins

If Sarah earned £80,000/year instead:

Plan 2 repayment:

• Income: £80,000
• Above threshold: £52,705
• Repayment: 9% × £52,705 = £4,743/year = £395/month
• Interest: £40,000 × 6% = £2,400/year
• Loan shrinking: £2,343/year (£4,743 repayment − £2,400 interest)
• Loan balance over 10 years: £40k → £20.7k (halved)
• Loan paid off in ~17 years (before 30-year write-off)

Now overpayment makes more sense:

• Overpay £200/month (total £595/month)
• Loan clears in ~13 years (vs 17)
• Saves interest for 4 years
• Interest saved: ~£9,600 (4 years × £2,400)
• Overpayment justified (saves £9,600)

Rule of thumb: If you earn >£60k, overpayment can save interest and is worth considering. If you earn <£50k, investing (not overpayment) is better.

Plan 2 vs Plan 5 Comparison

Most of you are Plan 2 (post-2012 graduates). But some have Plan 5:

Plan 5 (older loan):

• Threshold: £25,000 (vs £27,295 for Plan 2)
• Repayment period: 40 years (vs 30 for Plan 2)
• Interest: same 9% above threshold
• Effective interest rate: often 5–6% due to write-off after 40 years

Example: £50k loan on Plan 5, earnings £50k

• Repayment: 9% × (£50,000 − £25,000) = £2,250/year = £188/month
• Lower threshold (£25k vs £27.3k) means higher repayment for same salary
• But 40-year write-off (vs 30) means more of the loan is forgiven

For Plan 5 borrowers: Overpayment is even less attractive (longer write-off period makes the loan cheaper).

The Psychological Case for Overpayment

Even though the math says "don't overpay," some borrowers feel better clearing student loans:

• Psychological debt relief
• Improving credit score (no debt = higher score)
• Peace of mind

If you earn >£60k and the psychological benefit is worth £1,000–£2,000, overpayment is understandable (even if not optimal financially).

Overpayment Scenarios

Final Checklist: Should You Overpay?

• What's your income? If <£50k, skip overpayment
• Do you have emergency savings (6 months expenses)? If no, don't overpay
• Do you have credit card/high-interest debt? If yes, pay that first
• Can you invest in an ISA at 5%+ return? If yes, invest instead of overpay
• Do you earn >£60k and want psychological relief? If yes, overpay is acceptable
• Will you benefit from a lower loan balance (mortgage underwriting)? If yes, overpay helps

Default recommendation: For most UK graduates earning <£60k, don't overpay. Invest in ISA or clear higher-interest debt instead. Let the student loan run its course and be forgiven in 30 years.

Next step: Use the Student Loan Payoff calculator with your outstanding balance, interest rate, current monthly repayment, and any extra payment you are considering, to see what overpaying would save in interest. It models a conventional amortising loan, so it does not apply the income-contingent repayment threshold or the write-off date — judge those from the plan rules above. Most UK graduates under £50k income should not overpay; those over £70k should consider overpayment.