buy to let calculator — the short version

Use this Buy-to-Let calculator when you need a buy to let calculator you can trust — clean inputs, transparent steps, zero fluff.

We built Buy-to-Let calculator because the other tools for this job either cost a subscription or came with a consent banner the size of a small novel.

Lenders model this scenario with the same tools — no reason you should be in the dark. Think of the next 12 months in whole pounds or reais, not percentages — then run the sums and the rest of this page explains what the answer means.

Model a UK buy-to-let including stamp duty surcharge, mortgage, rental income, running costs and cash-on-cash return.

On this page you will see Buy-to-let, Section 24 and Cash-on-cash return treated as first-class terms — each one is linked to the calculators and references that use it, so you can follow the thread without retyping queries into a search bar.

If it helps, jump straight to the Finance hub or compare with the Rental Yield calculator and the Stamp Duty (Second Home) calculator — those two calcs are the ones readers usually open right after this page.

From inputs to answer, in full

Consider a realistic scenario and follow it through:

Model a UK buy-to-let including stamp duty surcharge, mortgage, rental income, running costs and cash-on-cash return.

Scenarios where Buy-to-Let calculator pays off

Buy-to-Let calculator is aimed at people arriving with questions like these:

"Buy to let calculadora UK"
"Btl stamp duty"
"Landlord tax calculadora"
"What is buy to let calculator"
"How to calculate buy to let calculator"
"Buy to let calculator formula"

When it isn't the right tool

Every tool has an edge where it stops being the right answer. Buy-to-Let calculator is no exception:

For legally binding tax or medical decisions — cross-check with HMRC, NHS or a qualified professional.
For very large or very small extremes the rounding error outgrows the useful precision.
When the underlying rate or threshold has changed since the page was last reviewed — always verify with the primary source.
When the input you have is already a derived figure (net of something) — feeding it in as "gross" will double-subtract.

Watch-outs before you trust the number

Every time you run the sums for a new scenario, one of these creeps in — it's worth knowing them ahead of time.

Flipping the numerator and denominator — half the "wrong" answers on this type of calculation are an inverted ratio.
Not noticing that one input is already pre-rounded by the source that gave it to you.
Forgetting that negative inputs behave differently — the formula assumes positive magnitudes unless the tool says otherwise.
Running the calculation once and believing it. Always sanity-check against an order-of-magnitude estimate done in your head.
Copying numbers from a PDF and picking up hidden thousands separators as decimal points.

The sources behind the numbers

Where the maths needs an external authority, we cross-check against:

HMRC
GOV.UK
Propertymark

Works well alongside

If this question keeps coming up for you, the same cluster of tools usually comes next:

Rental Yield calculator — Work out gross and net rental yield on a buy-to-let — including voids, service charge, agent fees and mortgage interest.
Stamp Duty (Second Home) calculator — Apply the UK 3% SDLT surcharge for second homes and buy-to-let purchases, with thresholds and relief explained clearly.
Mortgage Repayment Calculator — Estimate your monthly UK mortgage repayment from loan amount, interest rate and term — with total interest paid over the life of the mortgage.
Capital Gains Tax Estimator (UK) — Estimate CGT on shares, funds or other chargeable assets using the annual exempt amount and the correct rate band for your income — residential property uses different rates than other assets.

How we keep this accurate

Our calculadoras run on pure, unit-tested functions — the same logic lives in the browser and in the CI test suite. When tax rates, thresholds or official figures move, the update lands within 24 hours of the announcement. You can read the editorial policy and corrections policy.

Found an out-of-date number on Buy-to-Let calculator or anywhere else in the Finance toolkit? Send it to the editorial desk and we'll patch it. Or browse the full calculadora directory for the next tool you need.

Frequently asked questions

Buy to let calculadora UK?

Practically speaking, feed the figures into the Buy-to-Let calculator widget and it'll show the working. Model a UK buy-to-let including stamp duty surcharge, mortgage, rental income, running costs and cash-on-cash return.

Btl stamp duty?

Here's the plain-English summary: open the Buy-to-Let calculator widget at the top of the page. Model a UK buy-to-let including stamp duty surcharge, mortgage, rental income, running costs and cash-on-cash return.

Landlord tax calculadora?

In one line: this question usually arrives alongside Rental Yield calculator, Stamp Duty (Second Home) calculator, Mortgage Repayment Calculator. The Buy-to-Let calculator handles the specific case above; the others cover adjacent ground.

What is buy to let calculator?

Put simply, every figure is cross-checked against HMRC and the wider data. If you notice a stale rate, email the editorial desk and we'll patch it in under 24 hours.

How to calculate buy to let calculator?

The direct take: yes, everything runs in your browser. No inputs are sent to our servers or any third party, nothing is logged and nothing persists after you close the tab.

Buy to let calculator formula?

Straightforward answer: Buy-to-Let calculator is free to use, free to share and free to embed — pass the URL around a class, a slack channel or a family chat. The editorial policy covers attribution.

Buy to let calculator example?

Without the jargon, the short method: write the inputs in the units shown, run the calculation, then sense-check the answer against an order-of-magnitude estimate in your head.

Buy to let calculator worked example?

Tldr: if the result surprises you, run it a second time with slightly different inputs — small swings often reveal a unit or rounding issue in the original figures.

Buy to let calculator explained?

The useful way to think about it: a calculadora is a sanity check, not a verdict. For anything legally binding — contracts, tax filings, medical decisions — bring the figure to a qualified professional as a starting point.

Buy to let calculator definition?

Cutting to it, Model a UK buy-to-let including stamp duty surcharge, mortgage, rental income, running costs and cash-on-cash return. The page walks through the method in full so you can answer follow-up questions without guessing.

Buy to let calculator meaning?

Short answer: open the Buy-to-Let calculator widget at the top of the page. Model a UK buy-to-let including stamp duty surcharge, mortgage, rental income, running costs and cash-on-cash return.

Buy to let calculator step by step?

Quick version: open the Buy-to-Let calculator widget at the top of the page. Model a UK buy-to-let including stamp duty surcharge, mortgage, rental income, running costs and cash-on-cash return.

How it works