Self-Assessment Tax Calculator — Calculate Your Tax Liability

Self-Assessment Tax Calculator

Calculate your self-assessment tax liability with our comprehensive calculator. Determine tax owed, payment deadlines, and plan your finances based on your income and tax year.

Step 1: Income Details

Understanding Taxable Income

Taxable income includes all sources of income minus allowable deductions. Employment income, self-employment profits, dividends, interest, and rental income are all typically taxable.

Step 2: Deductions & Tax Year

£5,000
£3,000
£1,000
£12,570

About Tax Deductions

Allowable deductions reduce your taxable income. Pension contributions, legitimate business expenses, and charitable donations can significantly lower your tax liability.

Tax Calculation Results

Summary
Tax Breakdown
Payment Deadlines

Total Tax Liability

£12,432
For tax year 2024-2025 with £72,000 total income
Total Income
£72,000
Total Deductions
£9,000
Taxable Income
£63,000
Effective Tax Rate
19.7%

Tax Band Breakdown

Tax Band Income in Band Tax Rate Tax Amount

Self-Assessment Payment Deadlines

Important Tax Dates

Payment deadlines vary by tax year. Late payments may result in penalties and interest charges. Always check official government sources for exact dates.

First Payment on Account

50% of previous year’s tax bill

31 January 2025
Second Payment on Account

Remaining 50% of previous year’s tax bill

31 July 2025
Balancing Payment

Any remaining tax due for the year

31 January 2026

Tax Calculation Formula

Taxable Income = Total Income – Personal Allowance – Allowable Deductions

Tax is calculated by applying different rates to portions of your income within each tax band. Personal allowance is the amount you can earn tax-free each year.

Need Professional Tax Advice?

Connect with our tax experts for detailed tax planning, self-assessment filing assistance, and personalized tax strategies for your financial situation.

Get Professional Tax Help