Expert buy-to-let mortgage advice for property investors

Thinking about buying your first rental property or adding to your portfolio? The mortgage you choose can make a big difference to how the numbers stack up.

Residential property can be a lucrative investment for many, bringing in rental income as well as the potential of long-term property growth. If you’re looking to buy a property to rent out, rather than to live in, you need a specialist buy-to-let mortgage. Unlike standard residential mortgages, they are designed for landlords and have different eligibility criteria, deposit requirements, and repayment options.

Bennison Brown can help you understand your options, and find a competitive deal to help you get more from your property investment.

How buy-to-let mortgages are calculated

As part of the buy-to-let mortgage application process, the lender will assess your eligibility, arrange a property valuation, and estimate its potential rental income. This rental estimate matters because it plays a central role in determining how much you can borrow.

Typically, a lender will calculate the interest on your mortgage at a notional ‘stress rate’ (often 5.5%) to allow for potential future rate increases, then require your rental income to cover around 145% of that figure. This buffer is designed to account for costs like maintenance, tax, and possible void periods, helping to make sure the mortgage remains manageable even during quieter times.

As an example: £300,000 mortgage x 5.5% stress rate x 145% = £23,925 required rental income for the year (£1,994 per calendar month).

If the rental income doesn’t meet a lender’s criteria, the lender may consider “top slicing”, where they use some of your personal surplus income to make up a shortfall in the rental calculation. This may allow you to borrow more.

Some lenders may also apply a lower stress rate, particularly if you choose a five-year fixed rate or are purchasing through a limited company with which can also increase the amount you’re able to borrow.

buy to let property

Why choose Bennison Brown as your buy-to-let mortgage broker?

Whether you’re buying your first rental property or growing an existing property portfolio, we’ll take the time to understand your plans and find mortgage options that fit.

You can expect a dedicated adviser and case manager from start to finish, who has access to deals beyond those available directly from high-street lenders.

Our aim is simple: to make the buy-to-let mortgage process clearer and less stressful, while helping you make a well-informed decision about your investment.

Organise a free consultation with our mortgage advisers

Or email enquiries@bennisonbrown.co.uk

We look forward to speaking to you soon. We don’t use your details for marketing, only to get in touch and speak to you about your requirements.

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