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You’ve found your dream home and now just need to sort your finances. Here’s our breakdown of what you might pay monthly, including interest, over the life of a £100,000 mortgage.
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Monthly payments on a £100,000 mortgage
At a 4% fixed interest rate, your monthly mortgage payment on a 30-year mortgage might total £477.42 a month, while a 15-year might cost £739.69 a month.
Note that your monthly mortgage payments will vary depending on your interest rate, taxes and PMI, among related fees.
Your total interest on a £100,000 mortgage
On a 30-year mortgage with a 4% fixed interest rate, you’ll pay £71,869.51 in interest overall. That’s about two-thirds of what you borrowed in interest.
If you instead opt for a 15-year mortgage, you’ll pay £33,143.83 in interest overall, or about half of the interest you’d pay on a 30-year mortgage.
What is the total amount repayable?
When you take out a mortgage, you agree to pay the principal and interest over an agreed term. Your interest rate is applied to your balance and as you pay down your balance, the amount you pay in interest changes.
This means that at the beginning of your mortgage, a big percentage of your payment is applied to interest. With each subsequent payment, you pay more towards your balance.
Estimate your monthly repayments on a £100,000 mortgage at 4% fixed interest with our total amount repayable over 15 and 30 years.
| Year | Beginning balance | Total interest paid | Total principal paid | Remaining balance |
|---|---|---|---|---|
| 1 | £100,000.00 | £3,909.61 | £4,966.67 | £95,033.35 |
| 2 | £95,033.35 | £3,707.25 | £5,169.03 | £89,864.34 |
| 3 | £89,864.34 | £3,496.65 | £5,379.63 | £84,484.75 |
| 4 | £84,484.75 | £3,277.51 | £5,598.77 | £78,885.98 |
| 5 | £78,885.98 | £3,049.37 | £5,826.91 | £73,059.11 |
| 6 | £73,059.11 | £2,811.99 | £6,064.29 | £66,994.84 |
| 7 | £66,994.84 | £2,564.92 | £6,311.36 | £60,683.50 |
| 8 | £60,683.50 | £2,307.79 | £6,568.49 | £54,115.03 |
| 9 | £54,115.03 | £2,040.17 | £6,836.11 | £47,278.96 |
| 10 | £47,278.96 | £1,761.68 | £7,114.60 | £40,164.37 |
| 11 | £40,164.37 | £1,471.79 | £7,404.49 | £32,759.92 |
| 12 | £32,759.92 | £1,170.13 | £7,706.15 | £25,053.80 |
| 13 | £25,053.80 | £856.18 | £8,020.10 | £17,033.72 |
| 14 | £17,033.72 | £529.43 | £8,346.85 | £8,686.89 |
| 15 | £8,686.89 | £189.38 | £8,686.90 | £0.00 |
| Year | Beginning balance | Total interest paid | Total principal paid | Remaining balance |
|---|---|---|---|---|
| 1 | £100,000.00 | £3,967.95 | £1,761.09 | £98,238.96 |
| 2 | £98,238.96 | £3,896.19 | £1,832.85 | £96,406.18 |
| 3 | £96,406.18 | £3,821.53 | £1,907.51 | £94,498.73 |
| 4 | £94,498.73 | £3,743.82 | £1,985.22 | £92,513.56 |
| 5 | £92,513.56 | £3,662.94 | £2,066.10 | £90,447.51 |
| 6 | £90,447.51 | £3,578.77 | £2,150.27 | £88,297.29 |
| 7 | £88,297.29 | £3,491.15 | £2,237.89 | £86,059.47 |
| 8 | £86,059.47 | £3,399.97 | £2,329.07 | £83,730.48 |
| 9 | £83,730.48 | £3,305.09 | £2,423.95 | £81,306.59 |
| 10 | £81,306.59 | £3,206.35 | £2,522.69 | £78,783.96 |
| 11 | £78,783.96 | £3,103.56 | £2,625.48 | £76,158.55 |
| 12 | £76,158.55 | £2,996.62 | £2,732.42 | £73,426.17 |
| 13 | £73,426.17 | £2,885.29 | £2,843.75 | £70,582.48 |
| 14 | £70,582.48 | £2,769.43 | £2,959.61 | £67,622.93 |
| 15 | £67,622.93 | £2,648.85 | £3,080.19 | £64,542.80 |
| 16 | £64,542.80 | £2,523.36 | £3,205.68 | £61,337.18 |
| 17 | £61,337.18 | £2,392.76 | £3,336.28 | £58,000.96 |
| 18 | £58,000.96 | £2,256.84 | £3,472.20 | £54,528.82 |
| 19 | £54,528.82 | £2,115.38 | £3,613.66 | £50,915.22 |
| 20 | £50,915.22 | £1,968.16 | £3,760.88 | £47,154.39 |
| 21 | £47,154.39 | £1,814.93 | £3,914.11 | £43,240.34 |
| 22 | £43,240.34 | £1,655.46 | £4,073.58 | £39,166.83 |
| 23 | £39,166.83 | £1,489.52 | £4,239.52 | £34,927.36 |
| 24 | £34,927.36 | £1,316.79 | £4,412.25 | £30,515.16 |
| 25 | £30,515.16 | £1,137.01 | £4,592.03 | £25,923.21 |
| 26 | £25,923.21 | £949.95 | £4,779.09 | £21,144.17 |
| 27 | £21,144.17 | £755.23 | £4,973.81 | £16,170.42 |
| 28 | £16,170.42 | £552.61 | £5,176.43 | £10,994.04 |
| 29 | £10,994.04 | £341.70 | £5,387.34 | £5,606.76 |
| 30 | £5,606.76 | £122.23 | £5,606.81 | £0.00 |
A mortgage of £230,537 payable over 23 years, initially on a fixed rate until 31/01/28 at 3.99% and then on a variable rate of 6.49% for the remaining 21 years would require 24 payments of £1,277.66 followed by 252 payments of £1,585.00. The total amount payable would be £430,099 made up of the loan amount plus interest (£199,547) and fees (£15). The overall cost for comparison is 6.1% APRC representative.
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