Property and Landlord Tax UK 2026/27 — Rental Income, CGT, Relief and Filing

Landlord Tax Return Guide — Self Assessment Property Pages Step by Step

How to complete the property pages of your Self Assessment tax return as a UK landlord — reporting rental income, claiming expenses, and avoiding common mistakes.

Tax information is based on HMRC rules for the 2026/27 tax year. Tax rules can change — always verify current rates at GOV.UK. This is not tax advice. Consider consulting a qualified tax adviser for your personal situation.

If you are comparing rental-income reporting, landlord deductions, and property-specific filing strategy, start with the Property and Landlord Tax Hub for the full route map.

Filling in your first Self Assessment tax return as a landlord can feel overwhelming. Between rental income calculations, expense deductions, the Section 24 mortgage interest restriction, and Payments on Account, there’s a lot to get your head around.

The stakes are real: get it wrong and you could face HMRC penalties, pay more tax than you should, or miss valuable deductions you’re entitled to. Many landlords overpay simply because they don’t know what expenses they can claim or misunderstand how mortgage interest relief now works.

The good news is that once you understand the structure, completing the SA105 (UK Property) pages becomes straightforward. This guide walks you through every box, explains what you can and can’t deduct, shows you how to calculate your taxable profit correctly, and helps you avoid the common mistakes that trigger HMRC enquiries.

Whether you’re a first-time landlord or have been letting property for years but still find tax returns confusing, this step-by-step guide will help you complete your return confidently and correctly.

Read more: See our Self Assessment guide for a complete overview of this topic.

Do You Need to File?

SituationNeed to file?
Rental income over £1,000/yearYes — register for Self Assessment
Rental income under £1,000/yearNo — covered by the £1,000 property income allowance
Using the property income allowanceNo — but you can’t also claim expenses
Made a rental lossYes — must be reported to carry it forward
Rent-a-Room income under £7,500/yearNo — exempt under Rent a Room scheme
Overseas rental propertyYes — use SA106 instead of SA105
Joint property ownershipYes — each owner reports their share

Key Dates

DeadlineDate
Register for Self Assessment5 October following the tax year
Paper return deadline31 October following the tax year
Online return deadline31 January following the tax year
Tax payment deadline31 January following the tax year
Payments on Account (1st)31 January
Payments on Account (2nd)31 July

Step-by-Step: Completing SA105 (UK Property)

Section 1: Property Income

BoxWhat to enterNotes
Box 1Total rents and other income from propertyGross rental income for the tax year
Include rent, ground rent received, service charges received
Don’t include the deposit (unless you kept it as income)

How to Calculate Rental Income

IncludeDon’t include
Rent received from tenantsTenant deposits (held for return)
Rent owed but not yet received (accruals basis)Deposits kept as income — these ARE included
Service charges receivedInsurance claim payouts (capital)
Ground rent receivedSale of the property (this is CGT, not income)
Income from furnished holiday lets (if applicable)

Section 2: Property Expenses

BoxExpense typeExamples
Box 2Rent, rates, and insuranceGround rent, council tax (if you pay it), landlord insurance
Box 3Property repairs and maintenancePlumber, electrician, redecoration, replacing broken items
Box 4Finance costs (non-residential only)Mortgage interest on commercial property only
Box 5Legal, management, and other professional feesLetting agent fees, accountant, solicitor for tenancy disputes
Box 6Cost of services providedCleaning, gardening, communal area maintenance
Box 7TravelJourneys to the property for management/repairs
Box 8Other allowable expensesAdvertising for tenants, stationery, phone calls

Allowable Expenses — Full List

ExpenseDeductible?Notes
Letting agent feesYesMonthly management fee, tenant find fee
Landlord insuranceYesBuildings, contents, liability, rent guarantee
Ground rentYesLeasehold properties
Service chargesYesIf you pay them as landlord
Council taxYesOnly if you pay it (not if the tenant pays)
Utility billsYesOnly if you pay them (e.g. HMO)
Repairs and maintenanceYesFixing, repairing, redecorating
Replacing furnishingsYesReplacement of Domestic Items Relief
Accountant feesYesFor property tax work
Legal fees (letting-related)YesDrafting tenancy agreement, eviction costs
Advertising for tenantsYesOnline listings, signage
Travel to propertyYesMileage or public transport for management visits
Phone and stationeryYesReasonable proportion for property management
Mortgage interest (residential)No — tax credit onlySee Section 24 below
Mortgage interest (commercial)YesFull deduction
Capital improvementsNoAdding something new is not a repair
Your own labourNoYou can’t charge for your own time
Pre-letting expensesPartlyOnly if incurred within 7 years of first letting

Repairs vs Improvements

Repair (deductible)Improvement (NOT deductible)
Fixing a broken boilerInstalling a new boiler where none existed
Repainting wallsKnocking walls down to create open-plan
Replacing broken windows with like-for-likeUpgrading single glazing to double glazing
Fixing a leak in the roofAdding a loft conversion
Replacing worn carpet with similar qualityUpgrading carpet to hardwood flooring
Replacing a broken washing machineAdding a dishwasher for the first time

Principle: A repair restores to its original condition. An improvement makes it better than before.

Section 3: Mortgage Interest Tax Credit (Section 24)

BoxWhat to enter
Box 44Total residential finance costs (mortgage interest, loan interest, arrangement fees)

This is NOT deducted as an expense. Instead, you receive a 20% tax credit on this amount.

Section 24 Impact by Tax Band

Tax bandEffect
Basic rate (20%)No change — 20% relief matches 20% tax rate
Higher rate (40%)You pay 40% tax but only get 20% relief — net cost of 20% on mortgage interest
Additional rate (45%)You pay 45% tax but only get 20% relief — net cost of 25% on mortgage interest

Section 4: Calculating Profit or Loss

CalculationFormula
Total income (Box 1)e.g. £12,000
Minus total expenses (Boxes 2–8)e.g. £4,000
= Taxable profite.g. £8,000
Minus loss brought forwardFrom previous years
= Net profitTaxable amount
Tax credit (Box 44 × 20%)Reduces your tax bill (not your taxable income)

Example: Complete Tax Calculation

ItemAmount
Annual rent received£12,000
Letting agent fee (10%)–£1,200
Insurance–£300
Repairs–£800
Other expenses–£200
Taxable profit£9,500
Mortgage interest paid£4,000
Tax credit (20% of £4,000)–£800
If basic rate taxpayerCalculation
Tax on £9,500 at 20%£1,900
Less Section 24 credit–£800
Tax to pay£1,100
If higher rate taxpayerCalculation
Tax on £9,500 at 40%£3,800
Less Section 24 credit–£800
Tax to pay£3,000

Common Mistakes to Avoid

MistakeConsequence
Not registering for Self AssessmentLate registration penalties
Deducting mortgage interest as an expense (residential)Incorrect return — HMRC will correct and may charge penalties
Claiming improvements as repairsHMRC can disallow and charge interest
Not reporting void periods correctlyIncome only includes rent actually due, not void months
Forgetting Payments on AccountUnexpected cash flow demand in January and July
Not keeping recordsMust keep records for 5 years after the filing deadline

Record-Keeping

RecordKeep for
Rental income records (bank statements, tenant payments)5 years after filing deadline
Expense receipts and invoices5 years
Mortgage statements5 years
Tenancy agreementsDuration of tenancy + 5 years
Inventory and condition reportsDuration of tenancy + 5 years
Insurance policies5 years

Sources

  1. HMRC — Self Assessment tax returns
  2. HMRC — Renting out your property