Most people can get a buy-to-let mortgage if they have a deposit of around 25%, the expected rent comfortably covers the loan, and they meet the lender’s criteria. Many lenders also want you to already own your own home and earn a minimum income.
The short answer
- Expect to need a deposit of around 25%, with the best rates at 40%.
- Borrowing is driven mainly by the rent, stress-tested well above the pay rate.
- Most buy-to-let mortgages are interest-only, so plan how you will repay the capital.
A buy-to-let (BTL) mortgage is a loan for a property you intend to rent out rather than live in yourself. Lenders treat it very differently from a residential mortgage, because the loan is repaid largely from rental income rather than your salary. That changes how much you can borrow, the deposit you need, and the way the deal is assessed. The good news is that the market is competitive and, for most would-be landlords with a reasonable deposit and stable finances, a buy-to-let mortgage is achievable.
What lenders look for
Buy-to-let lending is assessed on the property’s earning power first and your personal circumstances second. The single biggest factor is whether the expected rent covers the mortgage payments with a healthy margin. Most lenders apply an interest cover ratio (ICR), stress-testing the rent against a notional interest rate. Typically they want the rent to be around 125% to 145% of the mortgage interest, calculated at a stressed rate of roughly 5.5% or higher, with the higher cover ratios usually applied to higher-rate taxpayers.
Beyond the rental calculation, lenders generally look for the following. Requirements vary widely, which is exactly where whole-of-market mortgage advice earns its keep.
Typical buy-to-let mortgage criteria in 2026 (illustrative, lenders vary)
| Requirement | Typical position |
|---|---|
| Deposit | Around 25% of the property value (some deals from 20%; the best rates often need 40%) |
| Rental cover | 125%–145% of the mortgage interest at a stressed rate |
| Minimum income | Many lenders want around £25,000 a year, though some have no minimum |
| Own home | Most prefer you to already own your residence; first-time landlord options exist |
| Age | Often up to 75–85 at the end of the term |
| Structure | Held personally or through a limited company (an SPV) |
Most buy-to-let mortgages are taken on an interest-only basis, meaning your monthly payment covers only the interest and the full loan is repaid when you eventually sell or remortgage. This keeps monthly costs low and rental profit higher, but it means the debt does not reduce over time, so you need a credible plan for repaying the capital. Lenders will also expect the property to be lettable and in reasonable condition; unusual construction, very short leases or a poor rental track record can all narrow your options. First-time landlords, in particular, tend to face a smaller pool of lenders and slightly stiffer terms, which is one reason many start with a straightforward, tenant-ready property rather than a project.
The tax picture matters
How you hold the property has become one of the most important decisions a landlord makes. Since the phasing-out of full mortgage-interest relief, individual landlords can no longer deduct finance costs from rental income in the old way. Instead you receive a basic-rate (20%) tax credit on your mortgage interest, which can push higher-rate taxpayers into paying considerably more tax than they expect on their rental profit.
Partly for this reason, many landlords, especially higher-rate taxpayers and those building a portfolio, now buy through a limited company (a special purpose vehicle). A company can still offset mortgage interest as a business expense and pays corporation tax on profits, though it faces its own costs and complexity. There is no universally right answer: the sums depend on your income, how many properties you own, and whether you draw the profits or reinvest them. This is genuinely a case for taking coordinated tax and mortgage advice before you commit.
Remember the extra Stamp Duty
Buying an additional residential property in England and Northern Ireland usually attracts a Stamp Duty Land Tax surcharge of 5% on top of the standard rates. On a typical rental purchase this can add thousands to your upfront costs, so factor it into your deposit planning from the start.
How much can you borrow?
Because affordability rests mainly on rent, two people with the same salary can borrow very different amounts depending on the property. A flat achieving £1,200 a month in rent supports a much larger loan than one achieving £800. This is the opposite of a residential mortgage, where the sums follow your income: you can read more about that in how to get a mortgage in the UK. If the rent does not stretch far enough, you can usually borrow less by putting down a bigger deposit.
Buy-to-let mortgage
- Deposit usually around 25%
- Borrowing based on rental income
- Usually interest-only
- Additional-property Stamp Duty applies
- Often arranged in a limited company
Residential mortgage
- Deposit can be 5%–10%
- Borrowing based on your income
- Usually capital repayment
- Standard Stamp Duty rules
- Held in your own name
A full explanation of rates, terms and portfolio lending sits in our guide to buy-to-let mortgages explained. If you are weighing up whether now is the right moment, the practical timeline in how long it takes to get a mortgage is worth a look, and landlords in the South West can find a local specialist through our Devon mortgage advisers.
Property values and rents can fall as well as rise, and being a landlord carries costs and responsibilities beyond the mortgage. This is information, not personal advice: a regulated adviser can tell you whether a buy-to-let plan stacks up for your circumstances.
In summary
- Expect to need a deposit of around 25%, with the best rates at 40%.
- Borrowing is driven mainly by the rent, stress-tested well above the pay rate.
- Most buy-to-let mortgages are interest-only, so plan how you will repay the capital.
- Tax treatment differs sharply between personal and limited-company ownership, take advice.
- Budget for the 5% additional-property Stamp Duty surcharge as an upfront cost.
Sources and further reading
- Mortgages MoneyHelper
- Mortgage rules and guidance Financial Conduct Authority
Read the full guide
For the complete picture, see our in-depth guide: Buy-to-Let Mortgages Explained.
Speak to a vetted mortgage advice specialist
This is free information, not personal advice. When you’re ready, we’ll match you with an independently vetted, FCA-regulated specialist, free, and with no obligation.
