UK buy-to-let & HMO calculator
Free rental property planning: compare yield, post-tax cash flow, ROI and the time to recover your upfront cash.
Your investment
Illustrative starting inputsStart here: enter your details
4 stages below. Scroll the fields, then choose Next.
The property basics
Start with the purchase price and a realistic rent.
£3,357 a year after running costs, mortgage payments and estimated tax.
Both cash figures are after running costs and mortgage interest only. No capital repayment is deducted. The post-tax figure also deducts estimated tax. Displayed amounts are rounded independently.
Start with the pressure points
Change an input. See what improves — and what gives.
Yield: Your 7.20% gross yield is 0.24 percentage points above the 6.96% overall buy-to-let lender-sample average. Your net yield is 5.85% before finance and tax.
Your money at work: For every £1,000 of upfront cash invested, this property generates approximately £56 a year before tax, after running costs and mortgage payments.
Cash payback: 22 years 2 months under the projection below.
Paragon Bank · Q1 2026 gross yields. Lender sample, not a local market valuation. Standard BTL uses the overall sample, including specialist properties; HMO uses the HMO sample. Gross yield is before costs, finance and tax. Benchmark checked 11 September 2026; not live data.
This scenario leaves £280 a month after tax and mortgage payments. Under your combined custom stress, post-tax monthly cash is -£16. Confirm 16 cost allowances before relying on the score.
Expand score breakdown & comparisonsCollapse score breakdown & comparisons
Temporary assumptions to explore, not suggested rents or offers.
How this assessment works
Points update in 0.1-point increments. Financial factors use the same thresholds for both strategies. Scoring always tests rent −10% and interest +2 percentage points (cash purchases have no rate shock), regardless of the custom stress settings below.
Saved comparison inputs last for this page session. Entering an allowance confirms only that you supplied it, not that it is accurate. Location, tenant demand, property condition and legal eligibility are not scored. This is a planning rubric, not a guarantee.
Post-tax cash payback
To recover £74,295 of upfront cash, including your opening reserve, from cumulative rental cash after tax.
By the recovery month: £74,412 cumulative post-tax cash — £74,295 repays your upfront investment and £117 is surplus. Monthly cash is averaged within each year.
First full year after recovery · year 24
Expand annual projection · 50 years
| Year | Rent collected | Running costs | Mortgage payments | Tax | Post-tax cash | Cumulative cash | Surplus after upfront |
|---|---|---|---|---|---|---|---|
| 1 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £3,357 | -£70,938 |
| 2 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £6,714 | -£67,581 |
| 3 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £10,071 | -£64,224 |
| 4 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £13,428 | -£60,867 |
| 5 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £16,785 | -£57,510 |
| 6 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £20,142 | -£54,153 |
| 7 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £23,498 | -£50,797 |
| 8 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £26,855 | -£47,440 |
| 9 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £30,212 | -£44,083 |
| 10 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £33,569 | -£40,726 |
| 11 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £36,926 | -£37,369 |
| 12 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £40,283 | -£34,012 |
| 13 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £43,640 | -£30,655 |
| 14 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £46,997 | -£27,298 |
| 15 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £50,354 | -£23,941 |
| 16 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £53,711 | -£20,584 |
| 17 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £57,068 | -£17,227 |
| 18 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £60,425 | -£13,870 |
| 19 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £63,782 | -£10,513 |
| 20 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £67,138 | -£7,157 |
| 21 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £70,495 | -£3,800 |
| 22 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £73,852 | -£443 |
| 23 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £77,209 | £2,914 |
| 24 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £80,566 | £6,271 |
| 25 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £83,923 | £9,628 |
| 26 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £87,280 | £12,985 |
| 27 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £90,637 | £16,342 |
| 28 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £93,994 | £19,699 |
| 29 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £97,351 | £23,056 |
| 30 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £100,708 | £26,413 |
| 31 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £104,065 | £29,770 |
| 32 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £107,422 | £33,127 |
| 33 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £110,778 | £36,483 |
| 34 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £114,135 | £39,840 |
| 35 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £117,492 | £43,197 |
| 36 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £120,849 | £46,554 |
| 37 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £124,206 | £49,911 |
| 38 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £127,563 | £53,268 |
| 39 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £130,920 | £56,625 |
| 40 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £134,277 | £59,982 |
| 41 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £137,634 | £63,339 |
| 42 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £140,991 | £66,696 |
| 43 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £144,348 | £70,053 |
| 44 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £147,705 | £73,410 |
| 45 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £151,062 | £76,767 |
| 46 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £154,418 | £80,123 |
| 47 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £157,775 | £83,480 |
| 48 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £161,132 | £86,837 |
| 49 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £164,489 | £90,194 |
| 50 | £13,846 | £2,150 | £7,500 | £839 | £3,357 | £167,846 | £93,551 |
Illustration, not a forecast: rents and fixed costs change once each year; vacancy rates stay constant. Tax is recalculated using fixed 2026–27 rules and unchanged other income, without carrying tax losses or finance relief forward. Repayment mortgages amortise and end at the entered term. Interest-only borrowing is assumed refinanced at the same rate with no fees, leaving the capital debt outstanding. No sale, capital growth or reinvestment is included. Rent increases must be achievable and legally permitted.
Follow the money
Full-year operating cash breakdown. Amounts are rounded independently.
Running costs-£2,150
Includes all running-cost categories; figures are rounded independently.
Upfront cash & annual tax detail
Repayment principal builds equity but reduces spendable cash. ROI excludes that equity gain and any property appreciation. Purchase costs are not deducted from ongoing rent. Company losses are not set against other profits in this estimate.
Give it a stress test
Monthly post-tax cashWhat happens when the assumptions move against you?
Each scenario recalculates tax and the first 12 loan payments. A rate increase has no effect on a cash purchase. These are scenarios, not forecasts or lender affordability tests.
How the calculations work
Enter your property, finance, running costs and tax details in the four stages. Choose a single-household letting or an HMO with separate rents for each room, then compare cash purchases, interest-only borrowing and repayment mortgages.
Rental yield: gross yield is scheduled annual rent divided by purchase price. Net yield deducts empty periods and running costs before dividing by purchase price; both are before finance and tax.
Cash profit and ROI: pre-tax cash deducts running costs and mortgage payments from collected rent. Post-tax cash also deducts estimated income or corporation tax. Cash-on-cash ROI divides annual cash profit by all upfront cash, including purchase costs and your opening reserve. Choose Pre-Tax or Post-Tax in the ROI box; the assessment translates pre-tax cash ROI into annual pounds per £1,000 invested, while the score uses post-tax ROI. Capital repayments and property price growth are not cash profit; company figures are before personal extraction tax.
Cash recovery: payback is when cumulative post-tax rental cash covers the upfront investment. Optional rent and cost growth start in year two. The projection holds tax rules and other income constant, and excludes a property sale or capital appreciation. The stress tests explore lower rents and, where relevant, higher mortgage rates; they are not lender affordability decisions.
Tax rules checked 9 September 2026; HMO guidance checked 10 September 2026. Operating figures use 2026–27 tax rules for a full 12 months, not a forecast of future tax years. No automated market data or AI provider is connected.
All non-tax example figures are editable planning estimates as at this date. Your price, rent and financing are illustrative until replaced. Net yield uses purchase price as its denominator and deducts all annual cash running costs. Assessment weights are design choices, not industry benchmarks.