Buy-to-let · ICR · yield · 2026 rules

Let the rent set the loan

Q: How much can I borrow on a buy-to-let mortgage?

Usually it depends on the rent. Lenders check that the rent covers the mortgage interest by a set ratio, typically at least 125%, at a stressed rate of at least 5.5% or the product rate plus 2 points. Loan-to-value limits also apply.

Q: Can landlords still deduct mortgage interest?

Individual landlords can't deduct mortgage interest from rental income. Instead they get a tax credit at the basic rate, currently 20%. From April 2027 property income will have its own tax rates, 22%, 42% and 47%, and the credit will be given at 22%.

Q: What stamp duty do I pay on a buy-to-let?

The standard rates plus 5 percentage points on every band in England and Northern Ireland, for properties of £40,000 or more.

Q: What changed for landlords under the Renters' Rights Act?

Since 1 May 2026 in England, section 21 no-fault evictions have ended, tenancies are periodic with no fixed end date, rent can only be raised once a year, and landlords can't take more than one month's rent upfront.

Q: What rental yield do I need?

There's no single figure, but the rent has to pass the lender's stress test, and after costs and tax it has to beat what the money could earn elsewhere. Use the calculator to see the gross yield and the loan the rent supports.

Buy-to-let lenders care less about your salary and more about the rent. Enter the price, the rent and your rate to see the loan the rent supports, the deposit, the yield and the stamp duty.

Updated 6 October 2026 · Figures sourced and linked

Run my numbers →Check the achievable rent ↗

125%Industry minimum interest cover ratioSource: Bank of England (PRA), updated January 2026

5.5%Minimum stress rate lenders must assumeSource: Bank of England (PRA), updated January 2026

+5%Stamp duty surcharge on every bandSource: HM Revenue & Customs, accessed October 2026

3.8%UK private rent growth, 12 months to August 2026Source: Office for National Statistics, 16 September 2026

Buy-to-let calculator

What the rent will support

Use a realistic rent, not the best case: lenders often ask for a letting agent's estimate. An online rental valuation is a quick starting point.

Property priceExpected monthly rentBuy-to-let mortgage rate5.50%

Lender's interest cover ratio

Maximum loan, roughly£166,400Limited by the rent: £1,300 a month must cover 125% of the interest at a stress rate of 7.50%.

Deposit

£83,600

Gross yield

6.2%

Interest-only

£763/mo

Stamp duty

£15,000

Stress rate is the higher of 5.5% or your rate plus 2 points, the PRA's minimum test for most buy-to-let lending; different rules apply to fixes of five years or more. Stamp duty includes the 5% additional-property surcharge (England and NI). Ignores fees, voids, letting costs and tax.

Landlords in 2026

Four rule changes to price in

Renters' Rights Act

In force in England since 1 May 2026: no section 21, periodic tenancies, one rent increase a year (GOV.UK). See the Renters' Rights Act guide.

Property income tax from April 2027

New property rates of 22%, 42% and 47%; finance cost relief at 22% (HMRC).

Stamp duty surcharge

5 points on top of every band since 31 October 2024 (HMRC).

Portfolio landlords

With four or more mortgaged buy-to-lets, lenders must apply specialist underwriting across the whole portfolio (PRA).

Letting agents

Run an agency? Answer every landlord call

Landlords shopping for buy-to-let finance are also shopping for an agent. Lettings Quest is an AI voice agent that answers estate and letting agency phones around the clock and books valuations; its guides cover AI for letting agents and AI for estate agents in the UK.

Lettings Quest is run by the same team as this site.

Questions

Straight answers

How much can I borrow on a buy-to-let mortgage?

Mostly it depends on the rent. Lenders check rent covers the interest by an interest cover ratio, with 125% the industry minimum, at a stressed rate of at least 5.5% or your rate plus 2 points (PRA SS13/16).

Can landlords still deduct mortgage interest?

Not as an expense. Individual landlords get a tax credit at the basic rate, 20% (HMRC). From April 2027 property income gets its own rates of 22%, 42% and 47%, with the credit at 22% (HMRC).

What stamp duty do I pay on a buy-to-let?

Standard rates plus 5 points on every band (HMRC). Stamp duty calculator →

What changed for landlords under the Renters' Rights Act?

Since 1 May 2026 in England: no section 21 evictions, periodic tenancies, one rent rise a year and no more than a month's rent upfront (GOV.UK). A plain-English summary is on Lettings Quest's Renters' Rights Act guide.

What rental yield do I need?

There's no single answer: the rent must pass the lender's stress test, and after costs and tax it must beat other uses of the money. The calculator shows both sides.

Sources

Where the numbers come from

We use primary sources only: the ABI, regulators and government. Figures were checked on 6 October 2026. Spot something out of date? The source link is the fastest way to check.

Bank of England (PRA). SS13/16: Underwriting standards for buy-to-let mortgage contracts. updated January 2026.
HM Revenue & Customs. Higher rates of Stamp Duty Land Tax. accessed October 2026.
HM Revenue & Customs. Tax relief for residential landlords: how it's worked out. accessed October 2026.
HM Revenue & Customs. Changes to tax rates for property, savings and dividend income. 26 November 2025.
Ministry of Housing, Communities and Local Government. Renters' Rights Act: an overview for landlords. 1 May 2026.
Office for National Statistics. Private rent and house prices, UK: September 2026. 16 September 2026.

Keep going

Mortgage repayment calculator →Monthly payments, total interest and what a rate change does, at today's average rates.How much can I borrow? →Income multiples, the 4.5× limit and the price range your deposit opens up.Stamp duty calculator →SDLT for home movers, first-time buyers and additional properties, band by band.Overpayment calculator →Interest saved and years knocked off by paying a little more each month.Tracker vs fixed →How far Bank Rate would have to rise before a tracker costs more than a fix.First-time buyer mortgages →Deposit, loan-to-value band, stamp duty relief and Lifetime ISA rules in one place.