Buy-to-let in 2026 is a fundamentally different proposition to what it was before 2017. The Section 24 restriction, which removed the ability for landlords to deduct mortgage interest from rental income before calculating tax, is now fully phased in. Combined with higher mortgage rates and additional Stamp Duty surcharges, the economics of leveraged residential property investment have deteriorated significantly for higher rate taxpayers. This does not mean buy-to-let is unworkable -- but it means naive analysis based on gross rental yield alone will lead to wrong conclusions. This guide provides the 2026 numbers, the full tax calculation, and an honest assessment of where BTL remains viable and where it does not. (Source: HMRC, Section 24 guidance; Finance Act 2015; Bank of England mortgage data)
Section 24 -- The Tax Change That Transformed BTL Economics
Before April 2017, residential landlords could deduct their full mortgage interest cost from rental income before calculating their income tax liability. A landlord receiving 18,000 pounds in annual rent and paying 10,000 pounds in mortgage interest was taxed on 8,000 pounds of profit. From April 2020, this deduction was entirely removed and replaced with a 20% tax credit on the mortgage interest. The same landlord now pays income tax on the full 18,000 pounds of rental income, then receives a credit of 2,000 pounds (20% of 10,000 pounds interest) against their tax bill. (Source: Finance Act 2015, Section 24; HMRC, landlord income tax guidance)
The impact depends entirely on the landlord's marginal income tax rate. For a basic rate taxpayer, Section 24 makes no difference in practice -- the 20% credit replaces what was previously a 20% deduction. For a higher rate taxpayer (40%), the change is devastating. The 40% deduction has been replaced by a 20% credit, meaning the effective tax cost of the mortgage interest has doubled. For many higher rate landlords with high loan-to-value mortgages, Section 24 has converted a profitable investment into a loss-making one on an after-tax basis, sometimes pushing landlords into a higher tax band through the addition of rental income even when the property generates no cash profit after mortgage costs. (Source: HMRC, Section 24 transitional provisions and worked examples)
Important If you are a basic rate taxpayer and your rental income pushes your total income above 50,270 pounds into the higher rate band, Section 24 creates a cascading effect: the portion of rental income in the higher rate band is taxed at 40% while the mortgage interest credit remains at 20%. This means some landlords with moderate salaries and profitable properties face effective tax rates on rental income above 40%. Model your total income including rental income before assuming Section 24 does not affect you. |
How BTL Mortgage Affordability Is Assessed
Buy-to-let mortgage affordability is assessed differently from residential mortgages. Most BTL lenders do not use your personal income as the primary affordability test. Instead, they require that the rental income from the property covers a minimum percentage of the monthly mortgage payment at a stressed interest rate. The standard test is that rental income must cover 125% of the mortgage interest at a stress rate of 5.5% or higher. Some lenders require 145% for higher or additional rate taxpayers, recognising the increased tax cost of rental income. (Source: Bank of England, PRA underwriting standards for buy-to-let lending, SS13/16)
Example affordability calculation on a 200,000 pound BTL mortgage: stress rate 5.5% interest only = 917 pounds per month. At 125% coverage requirement, minimum rent required = 917 x 1.25 = 1,146 pounds per month. At 145% requirement, minimum rent required = 917 x 1.45 = 1,330 pounds per month. If the property achieves 1,100 pounds per month in rent, it passes the 125% test but fails the 145% test -- meaning the maximum mortgage available at 145% coverage is (1,100 / 1.45) / (5.5% / 12) = approximately 164,000 pounds. (Source: Council of Mortgage Lenders now UK Finance, BTL affordability guidance)
Portfolio Landlord Rules -- Additional Requirements for 4+ Properties
Since October 2017, lenders applying PRA standards to portfolio landlords (those with four or more mortgaged BTL properties) must apply a more rigorous underwriting assessment. Portfolio landlords must provide a complete business plan covering all properties, a full asset and liability schedule, cash flow projections for the portfolio, and evidence that the portfolio as a whole is financially sustainable. Individual property stress tests must also consider the wider portfolio context. This requirement significantly increased the administrative burden of BTL borrowing for portfolio investors and caused several major lenders to withdraw from the portfolio landlord market entirely. (Source: Bank of England, PRA Policy Statement PS11/17)
Capital Gains Tax on Sale -- the 2024 Changes
The October 2024 Autumn Budget reduced the higher rate of Capital Gains Tax on residential property from 28% to 24%, and confirmed the basic rate at 18%. This reduction was broadly welcomed by landlords, though the rates remain significantly above the pre-2024 position for basic rate taxpayers (10% for basic rate, 20% for higher rate) that applied to non-residential assets. The annual CGT allowance was cut to 3,000 pounds from April 2024, meaning almost all disposal gains from investment property will be taxed. On a property purchased for 200,000 pounds and sold for 300,000 pounds (100,000 pound gain minus 3,000 pound exemption = 97,000 pound taxable gain), the CGT bill for a higher rate taxpayer is 23,280 pounds (24% x 97,000). For a basic rate taxpayer with sufficient other income the basic rate band has been used, the bill is the same. (Source: HMRC, CGT on residential property, Autumn Budget 2024)
EPC Requirements and the 2030 Proposal
All privately rented properties in England must currently have an Energy Performance Certificate rating of at least E to be legally let. Properties with F or G ratings cannot be legally let to new tenants and cannot have existing tenancies renewed. The government has proposed raising the minimum to C by 2030 -- this proposal has been the subject of significant consultation and has not yet been enacted in law, but landlords with properties currently rated D or E should be planning for potentially significant capital expenditure on energy efficiency improvements. A typical improvement from D to C might involve loft insulation, cavity wall insulation, a new boiler, or double glazing -- costs ranging from 2,000 pounds for basic measures to 20,000+ pounds for comprehensive retrofits. (Source: DLUHC, EPC regulations and proposals; MHCLG, consultation 2024)
Tip Before purchasing any property for BTL, commission an EPC assessment and get quotes for improvement work if the rating is below C. Factor the improvement cost into your purchase price negotiation. A D-rated property with a 10,000 pound path to a C rating requires a 10,000 pound lower purchase price to produce the same investment return as a C-rated property at full asking price. |
Disclaimer: This article is for information only and does not constitute financial or legal advice. Consult a qualified adviser for guidance tailored to your situation. |
Frequently Asked Questions
Is buy-to-let still worth it in 2026?
It depends entirely on the specific property, purchase price, mortgage rate, rental yield, and your tax position. In London where gross yields average 3-4% and BTL mortgage rates are 4.5-5.5%, cash flow is typically negative on a leveraged basis -- the property costs more to finance than it generates in rent before tax and maintenance. In some regional cities where gross yields are 6-8%, positive cash flow is achievable even at current rates. For basic rate taxpayers with modest mortgages in higher-yield areas, BTL can still produce acceptable returns. For higher rate taxpayers with high LTV mortgages in low-yield markets, Section 24 and current rates have made the investment financially unviable in most cases.
Can I avoid Section 24 by putting the property in a limited company?
Properties held in a limited company are not subject to Section 24 -- the company can still deduct mortgage interest as a business expense. This is why many new landlords since 2017 have purchased through limited companies rather than personally. However, the limited company structure has its own costs and complications: Corporation Tax on rental profits (currently 25% above 50,000 pounds profit), additional legal and accountancy costs, personal guarantees typically required for BTL mortgages to limited companies, and the eventual extraction of profits via salary or dividend attracting further income tax. The break-even point -- at which a limited company structure produces better after-tax outcomes than personal ownership -- depends on your income tax rate, the size of the mortgage, and your plans for distributing or retaining profits. Seek specialist tax advice before restructuring or before making your first corporate purchase. (Source: HMRC, Corporation Tax; Companies Act 2006)
What deposit do I need for a first buy-to-let property?
The minimum deposit for a buy-to-let mortgage is typically 25% of the property purchase price, producing a 75% LTV. Some lenders accept 20% deposits (80% LTV) but the rate premium for higher LTV BTL mortgages is significant and the rental income coverage test becomes harder to pass on a lower deposit with higher monthly interest costs. For portfolio landlords (4+ mortgaged BTL properties), many lenders require at least 35-40% deposit. A first BTL purchase with a 25% deposit is the practical standard. (Source: UK Finance, BTL lending statistics 2026)
Sources
- HMRC Section 24: gov.uk
- Bank of England BTL PRA Standards: bankofengland.co.uk
- HMRC CGT Residential Property: gov.uk/capital-gains-tax
- DLUHC EPC Regulations: gov.uk
