Let to Buy Explained: How to Keep Your Home and Buy Your Next One

Last reviewed and updated by Darren Shepherd: August 2026

Let to buy means switching your current mortgage to a buy to let arrangement so you can rent out your existing home, while getting a new residential mortgage on the property you are moving to, without having to sell first. It comes up a lot with people relocating for work, keeping a child in a good school catchment, or simply not wanting to lose a buyer's chain over timing. Here is how it actually works.

What let to buy actually means

Rather than selling your current home to fund the deposit and mortgage on your new one, you keep it, let it out to a tenant, and use the rental income to cover a new buy to let mortgage on that property. Separately, you take out a fresh residential mortgage on the home you are moving into, based mainly on your own income and affordability, the same as any other home mover.

You end up with two mortgages running side by side, one buy to let on the home you have left, one residential on the home you live in now.

Let to buy versus consent to let, a distinction worth getting right

These two terms get mixed up constantly, and they are genuinely different things.

• Consent to let is permission from your existing residential lender to rent out your home temporarily, usually without a full remortgage. It tends to suit short-term situations, working abroad for a year, moving in with a partner while you decide what to do with your old flat, that sort of thing. Lenders often charge a small fee or slightly higher rate for the period, and it is not usually intended to run indefinitely.
• Let to buy is a proper, permanent switch onto a dedicated buy to let mortgage product, priced and underwritten as a long-term rental, alongside a brand new residential mortgage on your next home. It suits people who intend to keep the original property as a rental for years, not months.

If you are not sure which one fits your situation, that is exactly the kind of question worth putting to a broker before you commit to either route.

Who tends to use let to buy, and why

• You need to move for work or family reasons and cannot wait for a sale to complete.
• You are relocating but want to keep a foothold in your current area, perhaps to move back one day.
• Your current home is in a strong rental area and you believe it is a better long-term asset let out than sold.
• You want to avoid the stress and cost of being stuck in a broken buying chain while waiting to sell.

How lenders assess a let to buy application

The two mortgages are assessed quite differently.

The buy to let side (your existing home): lenders focus mainly on the rental income the property can achieve, not your personal income. Most want the rent to cover somewhere between 125% and 145% of the mortgage payment, calculated at a stress-tested rate rather than the actual pay rate, to build in a safety margin. If the rental income falls short of that, some lenders will look at your wider personal income to top it up, others will not, so lender choice matters here.

The residential side (your new home): assessed largely like any other residential mortgage application, based on your income, outgoings and credit history. Some lenders will factor in the ongoing costs of the buy to let mortgage as a commitment when assessing what you can afford on the new one, so the two applications are not always entirely separate in practice.

The costs to budget for

Let to buy is rarely free of extra cost compared with a straightforward sale and move. The main ones to plan for:

• The stamp duty surcharge. Because you will own two residential properties at completion, the 5% additional property surcharge normally applies to your new purchase. See my full guide to the second home surcharge for exactly how that is calculated.
• Remortgage and product fees on switching your existing home onto a buy to let deal, arrangement fees on buy to let products can be higher than residential ones.
• Ongoing landlord costs if you use a letting agent, along with safety certificates, insurance, and maintenance you are now responsible for as a landlord rather than an owner-occupier.

The risks worth being honest about

Running two mortgages is real financial exposure, not a paperwork exercise. A void period with no tenant, an unexpected repair bill, or a change in your own income can put pressure on both properties at once. Rental income is also taxable, and because the let property is no longer your only home, you may face capital gains tax on any increase in its value when you eventually sell it. None of this means let to buy is a bad idea, only that it needs to be a considered decision, not just the quickest way to avoid a broken chain.

Is let to buy right for you

Worth considering: your existing home would rent well, you have a genuine reason to keep it rather than sell, and you have thought through what happens if it sits empty for a month or two.

Worth pausing on: you would only just cover the rental stress test, you have no appetite for being a landlord day to day, or the only reason you are considering it is to avoid a short delay in selling.

Let to buy can be a genuinely good route when you have a real reason to keep your current home and the numbers stack up on the rental side. It is a bigger commitment than a straightforward move though, two mortgages, two sets of responsibilities, and real costs to plan for upfront. Work through the rental stress test on your actual property before you commit to anything with the seller of your next home.

General information, not financial advice. Your home may be repossessed if you do not keep up repayments on your mortgage. Renting out a property brings its own legal responsibilities as a landlord.

Sources: GOV.UK, buying an additional residential property, MoneyHelper, buying a home.