Best UK Landlord Tax Calculators 2026

Updated September 2026 · Independent comparison, not sponsored

Landlord tax is more complex than employee or even standard self-employed tax, thanks to Section 24 mortgage interest restrictions, stamp duty surcharges, and Capital Gains Tax on sale. Here's how the main free UK tools compare for landlords specifically.
PayToolkitGOV.UK CalculatorNRLAMoneyHelper
Free✓✓Members only✓
No signup✓✓✗✓
2026/27 rates✓✓✓✓
Buy-to-let / rental income calculator✓✗Limited✗
Section 24 mortgage interest calculator✓✗✗✗
Stamp duty (SDLT) calculator✓✓✗✗
Capital Gains Tax on property calculator✓✗✗Limited
Rental yield calculator✓✗✗✗
Landlord expense tracker✓✗✗✗
Breadth of landlord content10+ tools & guidesFew (official only)Guides, no calculatorsGeneral guidance

The GOV.UK calculator handles basic stamp duty. NRLA (National Residential Landlords Association) offers strong guidance but its calculators sit behind membership. MoneyHelper is a trusted general finance resource but has limited landlord-specific tooling. PayToolkit combines free calculators covering Section 24, rental income tax, stamp duty and Capital Gains Tax with plain-English guides explaining the rules behind each number, so landlords can both calculate and understand their position.

Explore Landlord Tax Tools

FAQ

Does Section 24 affect all landlords?

Section 24 applies to individual landlords who own property personally. Landlords who hold property through a limited company are not affected in the same way, since mortgage interest remains a normal deductible business expense for companies.

Which calculator should I use for buy-to-let stamp duty?

Use a calculator that specifically accounts for the additional-property stamp duty surcharge, since buy-to-let and second-home purchases are charged at a higher rate than a main residence purchase.

Is landlord tax software worth paying for?

For a single property, free calculators and guides are usually sufficient. Paid software becomes more worthwhile once you're managing multiple properties, need Making Tax Digital compliance, or want integrated bookkeeping across a portfolio.

Methodology: Comparisons are based on each provider's own published pricing and feature pages as of September 2026. We link out to alternatives fairly and do not accept payment for placement in this comparison. If something here looks out of date, let us know.