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Monthly loan repayments, worked out for fifteen common amounts

Each example is worked with the same fixed-rate annuity formula, at a rate representative of that loan size — 9.9% on £5,000 down to 5.0% on £100,000, because unsecured lending gets cheaper as the amount rises. Every one opens in the calculator with its numbers already filled in.

Built and verified by Jogeswar, MSc, PMP — Tool CornerEvery figure on this page is generated from the formula, not entered by hand

Every example at a glance

Fifteen scenarios, each worked the same way at the rate shown. Tap a row to jump to the full breakdown.

LoanRateMonthlyTotal interestTotal repaid
£5,000 over 3 years9.9%£161.10£800£5,800
£10,000 over 5 years7.9%£202.29£2,137£12,137
£13,000 over 4 years7.7%£315.54£2,146£15,146
£15,000 over 5 years7.5%£300.57£3,034£18,034
£18,000 over 4 years6.9%£430.20£2,649£20,649
£20,000 over 5 years6.5%£391.32£3,479£23,479
£20,000 over 7 years6.5%£296.99£4,947£24,947
£25,000 over 5 years6.9%£493.85£4,631£29,631
£30,000 over 10 years6.5%£340.64£10,877£40,877
£35,000 over 5 years6.2%£679.91£5,794£40,794
£40,000 over 10 years5.9%£442.08£13,049£53,049
£50,000 over 10 years5.5%£542.63£15,116£65,116
£50,000 over 15 years5.5%£408.54£23,538£73,538
£60,000 over 10 years5.4%£648.19£17,783£77,783
£100,000 over 25 years5.0%£584.59£75,377£175,377

How it is worked out

Every row uses the standard fixed-rate annuity formula. The monthly rate is the annual rate divided by twelve, and the number of payments is the term in months:

M = P × r × (1 + r)n ÷ ((1 + r)n − 1)
  • P — the amount borrowed
  • r — the monthly rate for that example: its annual rate ÷ 12. At 7.9% that is 0.006583; at 5.0%, 0.004167
  • n — the number of payments: the term in years × 12
  • M — the monthly repayment

Total repaid is M × n; total interest is that figure minus the amount borrowed. The rate is deliberately not held constant across the table — a single rate would misrepresent what lenders actually charge, because unsecured pricing improves as the amount rises. Where two rows do share a rate they are directly comparable: £20,000 over 5 years and over 7 years are both at 6.5%, which isolates the effect of the term on its own.

Each example in full

Every card below opens in the Loan Calculator with its own numbers already filled in, so you can change one figure and see what moves.

£5,000 over 3 years

Monthly repayment
£161.10
Rate
9.9%
Total interest
£800
Total repaid
£5,800
Payments
36

A £5,000 loan over three years is a common size for a used car or a single large purchase, and it is small enough that the rate matters less than the term.

Open this one in the Loan Calculator →

£10,000 over 5 years

Monthly repayment
£202.29
Rate
7.9%
Total interest
£2,137
Total repaid
£12,137
Payments
60

£10,000 over five years sits at the point where most lenders' advertised rates start to improve, because the amount crosses the tier boundary many rate cards use.

Open this one in the Loan Calculator →

£13,000 over 4 years

Monthly repayment
£315.54
Rate
7.7%
Total interest
£2,146
Total repaid
£15,146
Payments
48

£13,000 over four years is the shape of a used-car loan taken just above the £10,000 rate break, where the advertised APR usually drops a notch but the four-year term keeps the total interest modest.

Open this one in the Loan Calculator →

£15,000 over 5 years

Monthly repayment
£300.57
Rate
7.5%
Total interest
£3,034
Total repaid
£18,034
Payments
60

At £15,000 the interest is large enough that a one-point difference in rate is worth shopping for — the comparison table below shows exactly how much.

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£18,000 over 4 years

Monthly repayment
£430.20
Rate
6.9%
Total interest
£2,649
Total repaid
£20,649
Payments
48

£18,000 sits in the band where lenders advertise their sharpest personal-loan rates, and four years is the shortest term most borrowers can service at this size.

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£20,000 over 5 years

Monthly repayment
£391.32
Rate
6.5%
Total interest
£3,479
Total repaid
£23,479
Payments
60

£20,000 over five years is the most-searched combination of the set, and the one where extending the term looks most tempting and costs most.

Open this one in the Loan Calculator →

£20,000 over 7 years

Monthly repayment
£296.99
Rate
6.5%
Total interest
£4,947
Total repaid
£24,947
Payments
84

The same £20,000 at the same rate, stretched to seven years. Comparing this page with the five-year one is the clearest illustration of what a longer term buys and costs.

Open this one in the Loan Calculator →

£25,000 over 5 years

Monthly repayment
£493.85
Rate
6.9%
Total interest
£4,631
Total repaid
£29,631
Payments
60

£25,000 is around the upper limit of most unsecured personal lending in the UK; above it, lenders usually want security, which changes the rate entirely.

Open this one in the Loan Calculator →

£30,000 over 10 years

Monthly repayment
£340.64
Rate
6.5%
Total interest
£10,877
Total repaid
£40,877
Payments
120

Ten years is a long time to hold consumer debt. The total-interest figure below is the number worth sitting with before agreeing to a term this length.

Open this one in the Loan Calculator →

£35,000 over 5 years

Monthly repayment
£679.91
Rate
6.2%
Total interest
£5,794
Total repaid
£40,794
Payments
60

£35,000 is above the usual unsecured personal-loan ceiling, so this size is typically a secured or homeowner loan — the rate shown is indicative of that market rather than a headline personal-loan APR.

Open this one in the Loan Calculator →

£40,000 over 10 years

Monthly repayment
£442.08
Rate
5.9%
Total interest
£13,049
Total repaid
£53,049
Payments
120

At £40,000 over ten years the interest approaches a meaningful fraction of the principal, which is why secured rates are usually worth investigating at this size.

Open this one in the Loan Calculator →

£50,000 over 10 years

Monthly repayment
£542.63
Rate
5.5%
Total interest
£15,116
Total repaid
£65,116
Payments
120

The same £50,000 over ten years rather than fifteen: a materially higher monthly payment, and far less interest paid over the life of the loan.

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£50,000 over 15 years

Monthly repayment
£408.54
Rate
5.5%
Total interest
£23,538
Total repaid
£73,538
Payments
180

A £50,000 balance over fifteen years behaves much more like a mortgage than a personal loan — most of the early payments are interest, not capital.

Open this one in the Loan Calculator →

£60,000 over 10 years

Monthly repayment
£648.19
Rate
5.4%
Total interest
£17,783
Total repaid
£77,783
Payments
120

£60,000 over ten years is usually a secured loan against property, which is why the rate is closer to a mortgage than to a personal loan.

Open this one in the Loan Calculator →

£100,000 over 25 years

Monthly repayment
£584.59
Rate
5.0%
Total interest
£75,377
Total repaid
£175,377
Payments
300

At mortgage scale and mortgage length, the total paid over the full term is roughly double the amount borrowed — which is the single most useful thing to know before comparing deals.

Open this one in the Loan Calculator →

What these figures do not include

  • Arrangement, broker and early-settlement fees. Where a fee applies, the APR is higher than the rate shown for that example.
  • Any rate that is not fixed for the whole term. A variable rate changes every figure on this page.
  • Insurance or add-on products sold alongside the loan.
  • The rate you would be offered, which depends on your circumstances. Every rate here is a representative illustration for that loan size, not a quote.

Frequently asked questions

Why does each example use a different rate?+

Because one rate across all fifteen would misrepresent the market. Lenders price small loans higher and advertise their keenest rates in the middle of their range, so each example carries a rate representative of its size — 9.9% at £5,000, 5.0% at £100,000. For a like-for-like comparison use the two £20,000 rows, both at 6.5%, where only the term differs. Any row opens in the calculator if you want to substitute a rate you have actually been offered.

Does a longer term ever cost less overall?+

No. On a fixed-rate loan a longer term always lowers the monthly payment and always increases the total interest. Compare £20,000 over 5 years (£391.32 a month, £3,479 interest) with the same loan over 7 years (£296.99 a month, £4,947 interest): £94.33 less each month, £1,468 more in total.

Do these figures apply to a mortgage?+

The formula is identical, but the pricing is not — secured lending is cheaper than unsecured, and mortgages carry fees, valuation costs and product-transfer rules that personal loans do not. The mortgage examples are worked separately.

Change any of the numbers

Further reading

This is a calculation, not financial advice

The 9.9% used here is an illustration chosen to make the arithmetic concrete, not a rate anyone has offered you. Real quotes depend on your circumstances, and fees, charges and early-settlement terms are excluded above. Tool Corner is not authorised by the Financial Conduct Authority and does not give financial advice.

The formulas on this page are verified against the sources listed below. Read the full disclaimer.

Sources & references

The annuity formula and the way lenders must express borrowing costs:

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