Let to buy mortgages

Let to buy is a way of moving home without selling. The current home is remortgaged onto a buy-to-let or consumer buy-to-let mortgage so it can be let, and often equity is raised from it to fund the deposit on a new home. A new residential mortgage then funds the purchase of the next home.

There is no single let to buy product. It is two mortgages arranged together, one on each property, and they may come from the same lender or from two different lenders. Many lenders process the two applications together so that both offers are in place before completion.

Lenders check two things: that the rent on the current home covers the buy-to-let mortgage at the lender's stress rate, and that the borrower can afford the new residential mortgage on their income. They also look at equity in the current home, credit history and the reason for letting rather than selling.

Where the home is let to a family member or the borrower moves out but has not been a landlord before, the buy-to-let side may be a consumer buy-to-let mortgage, which is regulated (FCA Handbook PERG 4.4, accessed 20 Oct 2026). How standard buy-to-let mortgages work, and the checks each lender applies, is covered in the guide on how buy-to-let mortgages work.

The amount raised on the current home depends on its value, the lender's maximum loan-to-value and the rent the property can earn. The new residential mortgage is assessed on income, outgoings and the deposit, which can include equity raised from the old home. Each lender sets its own limits.

Worked example (example figures, not market data): a home worth £300,000 with a £120,000 mortgage could be remortgaged to £180,000 at 60% loan-to-value if the rent passes the lender's test, releasing £60,000 before costs towards the next deposit. The rent needed rises with the loan, so the release can be smaller than the equity available.

Let to buy usually means two sets of mortgage fees, valuation and legal costs. Keeping the old home normally means the Stamp Duty Land Tax surcharge on additional property in England, 5 percentage points (GOV.UK, Stamp Duty Land Tax: higher rates for additional properties, accessed 20 Oct 2026), applies to the new home.

Rental income is taxable, and when the former home is later sold, Capital Gains Tax may apply to part of the gain. Some lenders also charge more for let to buy than for a standard remortgage. Rate and fee differences are explained on the buy-to-let mortgage rates page, and an accountant can explain the tax position.

Let to buy is often used when a sale would be slow or would not raise the price wanted, when a move is expected to be temporary, or when the owner wants to keep the property as a long-term investment. It turns the old home into a rental business, with the duties and costs of being a landlord.

Alternatives include selling first, using a bridging loan to buy before selling, or a consent to let from the current lender for a short period. Each has different costs and risks, and a specialist broker can compare let to buy with these options for a particular move.

Timing matters too. Both mortgages normally need to complete on the same day, so the lenders, solicitors and any chain on the new purchase have to work to one timetable, and tenants can usually only move in once the buy-to-let mortgage on the old home is in place.