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Buy-to-Let Mortgage Calculator

How much could you borrow?

No credit checks here! Simply fill out the information below to get your estimate!

Prefer to talk? Call our friendly team on 01473 356 284 or request a call back

Specialist Buy-to-Let Mortgage Calculator

Use our specialist buy-to-let mortgage calculators to get an instant estimate of your borrowing potential. Whether you are a first-time landlord, an HMO investor, or looking to refinance through a limited company, our tools provide fast results based on current rental yields and lender criteria. Just Mortgage Brokers' buy-to-let mortgage calculator gives prospective and existing landlords a fast, no-obligation way to gauge their borrowing potential before committing to an application. Because it runs without any credit checks, you can explore your options freely without leaving a footprint on your file, and results are based on current rental yields and lender criteria rather than generic assumptions. Specificity matters in buy-to-let, where lenders typically require rent to cover 125% to 145% of the monthly interest payments at a stressed rate, a calculation most people would struggle to replicate accurately by hand. The result is a realistic starting figure in under a minute, which helps you set a sensible budget, judge whether a deal stacks up, and arrive at a broker conversation already knowing roughly where you stand

cartoon illustration of two friends with suitcases, illustrating landlords utilizing an online buy-to-let mortgage calculator to achieve the financial freedom needed for travel and leisure

Holiday Let Mortgage Calculator

Estimate your borrowing potential based on seasonal rental income and projected yields for short-term holiday lets.
Calculate Holiday Let Borrowing
cartoon illustration of a business woman running with a briefcase, representing a busy property investor using a fast buy-to-let mortgage calculator to check rental yields on the go

Ltd Company BTL Calculator

Calculate how much your SPV or limited company could borrow for a property investment based on current tax stress tests.
Calculate Ltd Co Borrowing
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BTL Remortgage Calculator

Find out how much equity you could release or how much you could save by switching your current mortgage to a better rate.
Calculate Your BTL Remortgage
cartoon illustration of neighbors speaking to eachother from their individual flat windows, representing a property investor utilizing a buy-to-let calculator to analyze the residential flat market

HMO Mortgage Calculator

Work out your borrowing power for multi-room properties using specialised rental calculations for HMO investments.
Calculate HMO Borrowing
a cartoon illustration of a man showing his smartphone screen to a female friend who is holding her own phone, representing co-investors comparing data on a buy-to-let mortgage calculator to plan a joint rental property venture

FTB BTL Mortgage Calculator

See how much you could borrow to start your property portfolio, even if you don't currently own your own residential home.
Calculate FTB BTL Borrowing

Excellent

4.94 based on 158 reviews

William Baker
Star Empty

Verified user

I have used twice and both times were quick and efficient. The brokers were knowlegable and professional answered emails quickly, and there were no issues with either mortgage application.

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United Kingdom, 5 months ago

Camilla Parker-Mullins & Paul Parker

Verified user

Daniel and Yasmin at Just Mortgage Brokers have both been fantastic at helping us switch our mortgage providers at the end of our fixed terms, or assist with onward purchases when we have needed them. I’d highly recommend their services.

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United Kingdom, 5 months ago

Jonathan

Verified user

Wouldn't hesitate to recommend. Daniel at Just mortgage Brokers helped me get a mortgage in 2015 and then 10 years later he helps me secure a mortgage for my second house. Wouldn't go elsewhere. Many thanks.

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United Kingdom, 7 months ago

Claire & Richard

Verified user

Been using a few years now , always a pleasure to work with with Daniel and always finds us the best deal.

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United Kingdom, 7 months ago

Nathan & Erin

Verified user

Dan was fantastic from start to finish. It took him less than a day to secure us a mortgage offer on a competitive rate. Never a question he was unable to answer whether it was mortgage or life insurance related. Highly recommend, A1 service!

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United Kingdom, 10 months ago

Gary

Verified user

Daniel helped us again renewing our mortgage and was extremely helpful throughout the entire process. Emails were responded to promptly, and any queries we had were dealt with without hesitation. Highly recommend.

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United Kingdom, 10 months ago

Costas

Verified user

We were very happy with Daniel at Just Mortgages as he helped us with our mortgage journey.He was very helpful and the process was quicker then we expected.Excellent customer service and very professional....5 Star review for Just Mortgages!

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United Kingdom, 1 year ago

Yaser & Amanah

Verified user

Daniel was excellent, he really helped us get the right mortgage package. He helped me understand each package and rate. Daniel was very patient with me. Thank you Daniel! I honestly highly recommend

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United Kingdom, 1 year ago

Timothy

Verified user

As a Landlord with a large portfolio the number of products available are limited. Daniel was great identifying competitive products and we agreed to three buy to let mortgages which completed without any issues. All questions and responses were anwered in a timely and professional manner. I would recommend Daniel and Just Morgage Brokers.

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United Kingdom, 1 year ago

Verity

Verified user

Just Mortgage Brokers are very helpful and responsive. Would definitely recommend their services to everyone

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United Kingdom, 1 year ago

FREQUENTLY ASKED QUESTIONS

Unlike residential loans, borrowing is primarily based on the property’s expected rental income rather than your salary. Most lenders require the rent to cover between 125% and 145% of the monthly mortgage interest payments when tested at a “stressed” interest rate.

If you are investing in a specialist property type, the calculation can differ – we also advise on buy-to-let mortgages for student property, multi-unit freehold block (MUFB) mortgages, and expat buy-to-let mortgages.

Lenders apply a “stress test” to ensure you can still afford the mortgage if interest rates rise. They typically calculate affordability using a notional interest rate (often between 5% and 8%) rather than your actual product rate, unless you are fixing for five years or more.

You generally need a minimum deposit of 25%, giving you a 75% loan-to-value (LTV). While some specialist lenders offer 80% or even 85% LTV, these products often come with much higher interest rates and stricter rental cover requirements.

Yes, through a process called “top-slicing.” Some lenders allow you to use your surplus personal salary to make up for a shortfall in rental income, though you will still need to meet their minimum earned income requirements (usually £25,000 per year).

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01473 356 284