Updated: April 13, 2023
Buy-to-Let Mortgage Calculator
Looking to buy an investment property but not sure how much you can afford? Use our buy-to-let mortgage calculator to give you a better idea.

Author: Pete Mugleston - Mortgage Expert, MD
Updated: April 12, 2023
If you’re interested in buying a buy-to-let property or want to add to your portfolio you can use our buy-to-let calculator to find out whether your mortgage is affordable. Give it a try below.
Buy-to-Let Mortgage Calculator
Our buy-to-let mortgage calculator can show you how much your mortgage could cost you each month and overall. Simply enter the rental property value, deposit, anticipated monthly rent, interest rate, mortgage term and our caculator will do the rest.
Interest only:
Capital and repayment:
Loan to Value ratio (LTV):
Most lenders won't offer buy-to-let mortgages over a LTV of 80%.
Interest Cover Ratio (ICR):
Most lenders require rental income to be at least 125%-145% of the interest repayments for a buy-to-let mortgage.
Get started with a specialist buy-to-let broker to find out how much they could help you save on your monthly mortgage repayments.
The following topics are covered below...
How this calculator works
Our buy-to-let mortgage calculator helps you work out whether your mortgage is affordable by revealing your interest cover ratio (ICR), based on projected rental income.
Simply enter the property value, deposit amount, how much monthly rent you expect to generate, the term length and an interest rate, and the calculator will provide you with an ICR. Most mortgage lenders need this ratio to be anywhere between 125% and 145%.
As well as telling you whether the ICR is high enough to pass the affordability checks, this calculator also reveals your loan-to-value ratio and the cost of your mortgage payments.
Get Started with a Broker
Maximise your chance of approval with specialist advice from a mortgage expert
Why use our buy-to-let mortgage calculator?
First and foremost, because it’s great as a starting point on your mortgage journey. You can get a fair idea of whether your mortgage will be affordable before you start shopping around for deals.
Other advantages to this calculator include…
- It’s free to use and no personal data needs to be entered
- It can help you work out how much rent you will need to charge
- The results can help you plan and budget for the future
Things to consider
While, of course, it’s useful to have an idea of what you can afford to borrow, it’s important to remember that online calculators can only ever be a guide and should never be taken as a definitive answer.
Mortgage rates and terms will vary between lenders and individuals, depending on personal circumstances, and being told by a calculator that you can afford a mortgage does not guarantee acceptance.
The best thing to do if you’re looking to buy a rental property is seek the guidance of a buy-to-let mortgage broker. They will be able to assess your specific situation, consider your overall financial picture and provide accurate, bespoke calculations.
A broker who specialises in buy-to-let mortgages will have access to a wide range of lenders away from the high street, who otherwise might not be as easy to find, and they’ll be able to negotiate on your behalf to secure you the best possible rates.
Our Broker-Matching Service Guaranteed!
We want you to have complete confidence in our service, and get the best chance of securing your mortgage. We guarantee to get your mortgage approved where others can’t – or we’ll give you £100*

How to calculate your rental yield
We have a separate calculator that you can use for this. Enter the details for you property below and the tool below will present you with figures for gross and net rental yield.
Rental Yield Calculator
This calculator will show you the rental yield on your buy-to-let property using either the original purchase price - plus associated costs - or the current value. All you need to do is choose which option you want to base your calculation on and your monthly rental premiums.
Gross Rental Yield:
Net Rental Yield:
Now you've worked out what your current rental yield is, why not speak to a broker to see what buy-to-let mortgage/remortgage opportunities are available? With their expertise in this market they'll be able to identify a range of new deals which could reduce your mortgage payments and, as a result, improve your overall rental yield.
Reviews
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Excellent service, thanks you very much!
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Great- would recommend 👍🏻
Great, 5 star efficient service. Would recommend
Allen

Prompt, pleasant, thorough!
David was prompt helpful and thorough. Our case was particularly challenging and he still managed to secure a good deal for us!
Eric

Why use Online Money Advisor?
We offer a free broker-matching service that will handpick the right mortgage advisor for you, in this case a buy-to-let specialist with a track record of helping customers just like you.
Call us now on 0808 189 0463 or make an enquiry so we can match you with a mortgage broker who has experience in securing buy-to-let finance and set up a free, no-obligation chat between you and them today.
Ask Us A Question
We can help! We know everyone's circumstances are different, that's why we work with mortgage brokers who are experts in Buy-To-Let mortgages. Ask us a question and we'll get the best expert to help.


Pete Mugleston
Mortgage Expert, MD
About the author
Pete, an expert in all things mortgages, cut his teeth right in the middle of the credit crunch. With plenty of people needing help and few mortgage providers lending, Pete found great success in going the extra mile to find mortgages for people whom many others considered lost causes. The experience he gained, coupled with his love of helping people reach their goals, led him to establish Online Mortgage Advisor, with one clear vision – to help as many customers as possible get the right advice, regardless of need or background.
Pete’s presence in the industry as the ‘go-to’ for specialist finance continues to grow, and he is regularly cited in and writes for both local and national press, as well as trade publications, with a regular column in Mortgage Introducer and being the exclusive mortgage expert for LOVEMoney. Pete also writes for OMA of course!