UK buy to let remortgage tool

Buy To Let Remortgage Calculator

Calculate your new mortgage payment, rental coverage ratio, loan-to-value, equity position and remortgage affordability instantly. This page does more than a payment estimate. It helps you decide whether to remortgage, release equity, or wait.

UK buy to let focused Free instant results Updated for current lending standards

Calculator Inputs

Enter the core numbers first. Advanced options let you model lender stress tests, equity release and upfront costs.

Live Results Everything updates instantly while you type
Waiting for inputs
Enter your figures
Annual Mortgage Cost -
Gross Rental Yield -
Loan To Value (LTV) -
Current Equity -
Rental Coverage Ratio -
Stress-Test Payment -

Fill in your balance, rate, term, property value and rent to see whether the rental income is likely to cover the mortgage.

Equity Release Module

Maximum Borrowing At Chosen LTV -
Current Mortgage Balance -
Potential Equity Release -
Additional Borrowing Available -

Optional fees are shown in the calculation so you can see the likely cash needed to complete a remortgage.

Rate Comparison Table

Rate Monthly Payment Difference From Current
Enter your figures to compare payment changes.

This shows how much the monthly cost moves if the rate rises. It is useful for deciding whether to lock now or wait.

What If Rates Rise?

Scenario Monthly Payment Rental Coverage Ratio Affordability Status
The stress test will appear after you enter valid numbers.

Shareable Results

Enter your figures to generate a summary you can copy, print or save as a PDF.

Smart Insights Engine

Start here

The calculator will generate personalised recommendations once you enter the property value, mortgage balance, rate and rent.

Compare Buy To Let Mortgage Options

Use the figures above to compare fixed rates, tracker rates and different LTV thresholds before speaking to a lender or broker. If the payment only works at one rate and one coverage level, that is a sign to be cautious.

What Is A Buy To Let Remortgage?

A buy-to-let remortgage is when you replace an existing mortgage on a rental property with a new deal. Landlords usually do this to get a better rate, move from one lender to another, release equity, or change the repayment structure. This can be useful when your fixed rate is ending, if your property value has risen, or if you want to refinance more efficiently across a portfolio.

When Should You Remortgage A Buy To Let Property?

The best time depends on the numbers, not just the calendar. If your current rate is ending soon, if a lender will offer a meaningfully lower payment, or if you can unlock equity without damaging affordability, it may be worth moving early. It is also worth reviewing the deal if rental income has changed, if void periods are reducing your comfort buffer, or if interest rates have moved enough to change your affordability profile.

Buy To Let Remortgage Decision Checklist

Compare the whole switch, not just the headline rate. Start with the current lender's early repayment charge and exit fee, then add the new product fee, valuation, legal work and any broker fee. Divide that switching cost by the monthly saving to estimate how long it takes to break even; a cheaper monthly payment can still be poor value if you expect to sell or refinance again before that point.

CheckWhy it changes the decisionUseful CoryVu result
LTV after refinancingHigher LTV can narrow product choice and make equity release harder.Current LTV and maximum borrowing
Rental coverageLenders commonly assess borrowing against rent, often using a stressed interest rate rather than the initial payment.Coverage ratio and rate-rise scenarios
Total switching costsFees and early repayment charges can outweigh a lower rate.Monthly saving compared with your fee total
Cash flow after voids and costsA mortgage-only comparison can hide maintenance, management, insurance and empty periods.Stress-test the full rental cash flow
Repayment strategyMost buy-to-let borrowing is interest-only, so the capital still needs an exit plan.Balance, equity and proposed borrowing

Understanding Loan To Value (LTV)

Loan to value is the mortgage balance divided by the property value. A lower LTV normally signals less lending risk and can unlock more competitive products. A higher LTV can still work, but it may narrow lender choice and reduce how much equity you can safely release. This calculator shows the ratio immediately so you can judge whether you are inside common buy-to-let thresholds.

Rental Coverage Ratios Explained

Rental coverage compares your monthly rent to the monthly mortgage payment. If the coverage is 125%, the rent is 1.25 times the payment. MoneyHelper says buy-to-let lenders commonly expect rent to cover roughly 125% to 145% of mortgage repayments, but the actual interest coverage ratio and stress rate depend on the lender, borrower and product. Treat the calculator's threshold as a comparison aid rather than an approval rule. A stronger ratio generally gives more flexibility if rates rise or rent falls.

Can You Release Equity From A Buy To Let Property?

Yes, if the new mortgage remains within the lender's LTV limits. The calculator estimates the maximum borrowing at your chosen LTV and compares it with your current balance. That tells you whether there may be equity available to withdraw. Optional fees are included so you can judge the likely cash impact more realistically before you apply.

Frequently Asked Questions

What is a buy-to-let remortgage?

It is a new mortgage replacing your current one on a rental property, usually to change the rate, term, lender, or borrowing amount.

How is Loan To Value calculated?

LTV is calculated as mortgage balance divided by property value, then multiplied by 100.

Can I remortgage an interest-only mortgage?

Yes. Many buy-to-let deals are interest-only, although lender criteria and rental coverage tests still apply.

How much equity can I release?

That depends on the value of the property and the maximum LTV the lender will accept. The calculator estimates the headroom available before fees.

What rental income do lenders require?

Lenders commonly want rent to exceed the mortgage payment by a margin. Many use 125% as a guide, but the exact test depends on the lender and product.

What happens if interest rates rise?

Your monthly payment rises, which can push coverage lower and reduce the amount of spare cash in the deal. The stress test table shows the effect quickly.

How do lenders assess affordability?

Most look at rental income, stress-tested interest rates, LTV, the ownership structure and sometimes wider landlord finances.

Can I remortgage multiple properties?

Yes. Portfolio landlords often refinance several properties, though lenders may review the portfolio as a whole.

What is a good rental yield?

There is no single target. The right number depends on the area, running costs, tax position and the mortgage product you can secure.

Can I remortgage before my fixed rate ends?

Sometimes, but you may pay an early repayment charge. Compare that fee against the saving from the new deal.

What is rental coverage ratio?

It is the monthly rent divided by the monthly mortgage payment, multiplied by 100. Higher is better for affordability.

Does gross yield include costs?

No. Gross yield is a simple headline figure and does not include voids, maintenance, management fees, tax or mortgage fees.

Can this help with equity release planning?

Yes. It shows the headroom between your current balance and the borrowing limit at your chosen LTV.

Is this a mortgage offer?

No. It is an estimate and should be used to compare options, not as a guaranteed quote.

How should I use the stress test results?

Use them to judge whether the deal still works if rates rise. If the rental coverage quickly falls below lender thresholds, that is a warning sign.

Trusted Reference

Last updated: 2026-07-22. This page gives an estimate only and is not legal, tax, financial, or employment advice.