Guide · Debt
Understanding Loan Repayments: APR, Monthly Payments, and the Total You'll Pay
A loan that looks affordable monthly can cost thousands more than you expect when you add up the total interest. Here is how to read a loan offer properly, compare APRs, and understand exactly what you are committing to.
How loan repayments work
Personal loans are repaid through fixed monthly instalments over a set term — typically 1 to 7 years. Each payment splits into two parts: interest charged on the outstanding balance, and principal repayment (reducing what you owe).
In the early months, a larger share of each payment goes to interest. As the balance reduces, interest charges fall and more of each payment reduces the principal. This is called amortisation. By the final payment, almost all of it is principal.
The true cost: how APR and term combine
The monthly payment is not the best measure of a loan's cost. A longer term lowers the monthly payment but dramatically increases the total interest paid. For a £10,000 loan:
| APR | Term | Monthly payment | Total repaid | Total interest |
|---|---|---|---|---|
| 7% | 3 years | £309 | £11,122 | £1,122 |
| 7% | 5 years | £198 | £11,880 | £1,880 |
| 12% | 3 years | £332 | £11,955 | £1,955 |
| 12% | 5 years | £222 | £13,333 | £3,333 |
| 20% | 5 years | £265 | £15,894 | £5,894 |
At 20% APR over 5 years, you repay nearly 59% more than you borrowed. Shorter terms cost less overall — the lower monthly payment of a longer term is an illusion of affordability.
What affects your APR
Lenders price loans based on the risk of default. Key factors include:
- Credit score — The biggest single factor. A high Experian/Equifax/TransUnion score unlocks lower rates.
- Loan amount and term — Larger, shorter-term loans sometimes attract better rates.
- Employment stability — Permanent employment is viewed more favourably than self-employment or contract work.
- Existing debts — High existing debt-to-income ratios result in higher rates or declined applications.
Overpaying and early repayment
If your loan allows overpayments without penalty, making regular extra payments significantly reduces total interest and shortens the term. On a £10,000 loan at 7% APR over 5 years, adding £50/month to the payment saves around £300 in interest and clears the loan 8 months early.
If your lender charges an Early Repayment Charge (ERC) — typically 1–2 months' interest — calculate whether the interest saving exceeds the charge before making a lump-sum repayment. It almost always does for loans with more than 12 months remaining.
Frequently asked questions
What is APR and how does it differ from the interest rate?
APR (Annual Percentage Rate) includes the interest rate plus any compulsory fees charged by the lender — arrangement fees, broker fees, account fees. It is the standardised cost of the loan designed for easy comparison. The representative APR shown in adverts must be offered to at least 51% of successful applicants. Your actual APR may be higher if your credit score is lower.
How is the monthly repayment calculated?
Personal loans use an amortisation schedule: each monthly payment covers both interest and a portion of the principal. Early payments are mostly interest; later payments are mostly principal. The formula is: M = P × (r(1+r)^n) ÷ ((1+r)^n − 1), where M is the monthly payment, P is the principal, r is the monthly interest rate, and n is the number of months.
What is the difference between a secured and unsecured loan?
An unsecured personal loan requires no collateral — approval is based on your creditworthiness, and rates are higher to reflect the lender's risk (typically 5–25% APR). A secured loan is backed by an asset (usually your home) — the lender can repossess it if you default. Secured loans offer lower rates but put your property at risk.
Is there a penalty for repaying a loan early?
Many personal loans charge an Early Repayment Charge (ERC) — typically 1–2 months' interest. Under FCA rules, for regulated loans you must be told the ERC before you sign. It is often worth paying if the interest saving exceeds the charge. Some lenders offer 'no early repayment charge' loans — worth prioritising if you think you might pay off early.