Quick answer
Most buy-to-let lenders commonly cap borrowing at 75% LTV — a deposit of roughly 25%. A smaller number of lenders offer products up to 80% LTV (around a 20% deposit), typically priced noticeably higher than 75% products. Deposits of around 40% or more typically move you into the strongest pricing tiers the market offers.
These are typical ranges, not guarantees available to every applicant — the LTV a lender actually offers you also depends on the rental-cover (ICR) test, the property type, your landlord experience, and your credit history.
In this guide
How much deposit do you need for a BTL mortgage?
Buy-to-let deposit requirements are typically expressed as a maximum loan-to-value (LTV) — the largest proportion of the property's value a lender will lend against, with the remainder coming from your deposit. Across the market, three broad bands are commonly seen:
- 75% LTV (around a 25% deposit) — the level most buy-to-let lenders treat as their standard maximum, and typically the widest choice of products and rates sits here.
- 80% LTV (around a 20% deposit) — offered by a smaller group of lenders, usually at rates noticeably higher than the equivalent 75% product, reflecting the extra risk the lender is taking on.
- Around 40% deposit or more — typically unlocks the lowest-LTV pricing tiers, where rates are commonly at their most competitive.
These are typical patterns across the market rather than fixed rules that apply to every lender or every applicant — treat them as a starting point for planning, not a quote. Our buy-to-let mortgage affordability guide covers how lenders assess what you can borrow in more depth.
Why the advertised maximum LTV isn't the whole story
A lender advertising “up to 80% LTV” is stating a ceiling, not a promise. Separately from the LTV cap, buy-to-let lenders typically apply a rental cover test— usually called the Interest Coverage Ratio (ICR) — which checks that the rent a property achieves comfortably exceeds the mortgage interest, calculated at a notional stress rate rather than the actual pay rate. A common requirement is rent equal to somewhere in the region of 125%–145% of the interest payment at that stress rate.
The two tests work independently, and whichever one produces the smaller loan is typically the one that governs how much you can actually borrow. A property with modest rental income relative to its value can find the ICR test caps borrowing at, say, 60–70% LTV even on an 80% LTV product — the advertised maximum simply never becomes available because the rent can't support that much debt.
Illustration only — not a quote
Take a property worth £200,000 achieving £950 a month in rent, tested at a 145% ICR and a 5.5% stress rate. Annual rent is £950 × 12 = £11,400. Dividing that by (1.45 × 0.055) gives roughly £143,000 as the loan size the rent supports — around 72% LTV, not the 80% the headline product might advertise. The maths and the figures here are for illustration only; actual ICR percentages, stress rates and results vary by lender and by your individual circumstances.
The practical implication: before assuming you can borrow up to a lender's maximum advertised LTV, it is worth checking what the property's actual achievable rent supports under a realistic ICR calculation. Sometimes a larger deposit is not a choice made for a better rate — it is simply what the rental income requires.
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Start My Free CheckHow loan size affects the maximum LTV
Many buy-to-let lenders don't apply a single maximum LTV across every loan size — they typically tier it. A common pattern is offering their highest LTV, such as 80%, only up to a certain loan amount, then reducing the maximum to 75% or lower once the loan size passes a given threshold. The logic is straightforward risk management: a larger loan represents more exposure for the lender, so it is commonly required to sit in a lower-risk (lower LTV) band.
These thresholds and tiers vary between lenders and change over time, so it isn't possible to state a single figure that applies market-wide. The practical takeaway is that a higher-value property, or a larger loan, may not be eligible for the same maximum LTV as a smaller one, even at the same lender. Running your actual numbers through a buy-to-let mortgage calculator is generally more reliable than assuming a headline maximum LTV applies to your loan size.
What else affects how much deposit you need
Beyond the headline LTV and the rental-cover test, several other factors commonly influence the deposit a lender will actually require:
- Property type. HMOs, flats (particularly above commercial premises or of non-standard construction) and new-build flats are typically treated as higher risk, and lenders commonly reduce the maximum LTV — and so increase the deposit needed — for these property types compared with a standard buy-to-let house.
- First-time landlord status. Some lenders reduce their maximum LTV, or decline certain property types such as HMOs altogether, for applicants with no existing landlord experience. Our first-time landlord mortgage guide covers this in more detail.
- Adverse credit. Missed payments, defaults or historic arrears typically reduce the maximum LTV a lender will offer, and can narrow the pool of lenders willing to consider the application at all.
- Limited-company borrowing. Buying through a special purpose vehicle (SPV) is common practice, but the range of lenders and the maximum LTV on offer can differ from personal-name borrowing, and is worth checking rather than assuming it mirrors personal-name terms.
- Holiday lets. Holiday-let mortgages are typically assessed as a distinct product line, often with a lower maximum LTV than standard buy-to-let, and rental income is usually assessed against projected nightly or seasonal income rather than a standard monthly tenancy rent figure.
Where the deposit can come from
Buy-to-let deposits typically come from one of a few common sources, and lenders tend to treat each somewhat differently:
- Savings. The most straightforward source, usually requiring the fewest additional checks beyond the standard source-of-funds and anti-money-laundering evidence every lender requires.
- Equity or remortgage of another property. Releasing equity from an existing property — including your own home, sometimes as part of a let-to-buy arrangement — is a common way landlords fund a BTL deposit, typically via a further advance or a remortgage that raises capital.
- Gifted deposits.Gifted deposits are commonly more restricted for buy-to-let than for a residential mortgage. Many lenders limit the proportion of a BTL deposit that can be gifted, or decline gifted deposits for buy-to-let altogether, reflecting that the property is an investment rather than the applicant's home. Where gifts are accepted, they are typically most readily accepted from close family members, and usually require a signed gifted-deposit letter confirming the gift is non-repayable and the donor has no interest in the property.
80% LTV buy-to-let: an honest look
80% LTV buy-to-let mortgages genuinely exist, and for some landlords with strong rental yields they are a realistic option. But it is worth being honest about the trade-offs before planning around one. The pool of lenders offering 80% LTV is typically smaller than at 75%, rates are commonly noticeably higher to reflect the extra risk, and — as covered above — the rental-cover test tends to bite hardest exactly at this end of the market, because a larger loan needs proportionally more rent to clear the ICR calculation.
In practice, many landlords considering an 80% LTV product find that a 75% product, combined with whatever loan size the property's actual rent supports, ends up being the realistic ceiling rather than the higher advertised maximum. That isn't a reason to rule out 80% LTV products outright — it's simply worth checking the numbers on your specific property rather than assuming the headline LTV is what you will be offered.
Frequently asked questions
Can I get a buy-to-let mortgage with a 10% deposit?
Effectively no, not in the mainstream buy-to-let market. Buy-to-let lending is assessed differently from residential lending — the loan size is checked against the rental income the property can achieve, not primarily against your salary, and lenders build in a substantial equity buffer to protect against void periods and rate rises. In practice that means the market's outer edge sits around 80% LTV (a 20% deposit) among a smaller group of lenders, and even then the rental-cover test frequently reduces what you can actually borrow. A 10% deposit is not a configuration the buy-to-let market is typically built to lend against.
Is there such thing as a 100% LTV BTL?
Not as a standard product. Buy-to-let mortgages are secured purely against the rental property and the income it produces, so lenders typically require meaningful equity from day one to absorb valuation movement, void periods and arrears risk. Some family-assisted or guarantor-backed structures exist in niche corners of the market, but a mainstream 100% LTV buy-to-let product is not something you should plan around.
Does a bigger deposit always mean a better rate?
Generally, yes, in the sense that lower-LTV pricing tiers are typically cheaper — moving from 80% to 75%, or from 75% down towards 60%, commonly unlocks better rates as you move into a lower risk band. But it is not a straight line: rate cards are typically split into bands (for example around 60%, 65%, 70%, 75% and 80% LTV), so a deposit increase only helps once it crosses into the next band down, and the improvement in rate needs weighing against how much extra cash is tied up. It is not a guarantee that any specific extra deposit amount will move you into a materially better rate.
Can I use equity from my home?
Often, yes. Releasing equity from your residential home, or from another property you already own, is one of the more common ways landlords fund a buy-to-let deposit — typically done through a further advance or a remortgage that raises capital. The same principle applies when you are moving your own home into a let and buying a new residence, sometimes described as let-to-buy. Our let-to-buy guide covers how that route works and what lenders typically look for.
Last updated: August 2026
