UK Tax Planning Calculators

Tax planning is not just for the wealthy. Every UK taxpayer can benefit from understanding how income tax, National Insurance, and allowances interact. The difference between proactive planning and simply accepting whatever HMRC calculates can amount to thousands of pounds over a tax year.

Start with the basics. The income tax calculator breaks down your earnings across the personal allowance, basic rate, higher rate, and additional rate bands using current 2026/27 thresholds. The salary calculator goes further, showing your take-home pay after income tax, National Insurance, student loan deductions, and pension contributions. For those with two employment sources, the tax code checker helps verify that HMRC has split your personal allowance correctly -- a common source of over-payment.

National Insurance is often overlooked in tax planning because it is deducted automatically, but it significantly affects your net income. Our NI calculator models both employee and self-employed contributions, including the different Class 2 and Class 4 rates that apply to sole traders. If you run your own business, the self-employment tax calculator brings income tax and NI together to show your total liability, while the self-assessment calculator helps you estimate your January payment.

For business owners, corporation tax is the headline figure. The corporation tax calculator models the current rate and marginal relief band, so you can see how retained profits translate to tax liability. Dividend tax then applies when you extract those profits -- our calculator factors in the reduced dividend allowance and the three dividend tax bands.

Tax-efficient saving is one of the simplest ways to keep more of what you earn. The ISA calculator shows how tax-free growth compounds over time compared to a taxable account, while the pension calculator models the impact of tax relief at your marginal rate -- effectively free money from the government. The pension tax relief calculator drills deeper into how much the government tops up based on your contribution level.

Marriage allowance transfers unused personal allowance between spouses, saving eligible couples up to several hundred pounds a year. The child benefit tax charge calculator shows higher earners how much of their child benefit they will need to repay through self-assessment. On the inheritance side, our IHT calculator models the nil-rate band, residence nil-rate band, and taper relief to estimate what your estate would owe.

Council tax rounding out the picture, our band calculator helps you check whether your property is in the correct valuation band -- a surprisingly common source of overpayment that can be reclaimed.