Buy-to-Let Tax Calculator

Buy to Let Tax Calculator helps you model a UK tax scenario using the selected tax year and a live result panel. Estimate UK buy-to-let tax for 2025/26 with rental income, expenses, mortgage interest and Section 24 relief. This version is designed for 2025/26 and 2026/27 planning, so it is useful when you want a fast decision-support tool before reviewing payroll documents, Self Assessment entries, or adviser notes.

Start with Annual Rental Income, Allowable Expenses (Excluding Mortgage Interest), Annual Mortgage Interest and related options. In most cases you should use annual gross figures unless the label clearly asks for monthly amounts, percentages, or a plan selection. Choosing the right tax year matters because thresholds, allowances and repayment bands can move, and many users get better results by checking their payslip, P60, pension statement, or loan plan first rather than estimating from memory.

Use the result as a planning view rather than a final filing number. The output is strongest when you compare scenarios, such as changing pension contributions, testing a different income level, or checking whether a threshold like the £12,570 personal allowance or £50,270 higher-rate point changes the outcome. If the result affects a real filing, payroll setup, or household decision, validate it against official records.