Official HMRC
Tax Rates & Compliance
All calculations use official HMRC tax rates and thresholds, updated within 24 hours of any changes.
- 100%HMRC Rates
All rates sourced from official publications
- 24hrsUpdate Time
New rates applied within 24 hours of announcement
- 4+Years Data
Historical rates back to 2020/21 tax year
HMRC Compliance Standards
How we ensure calculation accuracy
Official HMRC Tax Tables
All calculations use official HMRC tax rates and thresholds published for each tax year
- Income tax bands and rates verified against HMRC publications
- National Insurance rates updated for Class 1 contributions
- Student loan thresholds for all plan types (1, 2, 4, 5, Postgraduate)
- Scottish tax rates independently verified against Revenue Scotland
Formula Verification
Calculation formulas verified against official HMRC examples and test cases
- Tested against HMRC published example calculations
- Formulas match official PAYE calculation methods
- Edge cases validated against gov.uk guidance
- Open source for professional review and verification
Regular Updates
Tax rates and thresholds updated immediately when HMRC announces changes
- Autumn Budget updates within 24 hours
- Spring Statement changes applied same day
- Emergency rate changes implemented immediately
- Historical rates maintained for comparison
Quality Assurance
Multi-layer testing and validation ensures calculation accuracy across all scenarios
- Automated testing against HMRC examples
- Manual verification of edge cases
- Cross-platform calculation consistency
- Professional user feedback integration
Official Compliance Statements
Verified against UK tax law and regulations
Tax Rate Accuracy
All tax rates are sourced directly from official HMRC publications and updated within 24 hours of any announced changes.
Verified against HMRC Income Tax rates and allowances (ITTOIA 2005)
Last verified: 2024-08-25
National Insurance Compliance
National Insurance calculations follow official HMRC guidance for Class 1 contributions including current rates and thresholds.
Compliant with National Insurance Contributions Act 2014 and subsequent updates
Last verified: 2024-08-25
Student Loan Accuracy
Student loan calculations are accurate for all current repayment plans as defined by the Student Loans Company.
Verified against SLC guidance and HMRC PAYE procedures
Last verified: 2024-08-20
Scottish Tax Compliance
Scottish tax calculations use official rates published by Revenue Scotland and Scottish Government.
Compliant with Scotland Act 2016 and Scottish Rate Resolution
Last verified: 2024-08-15
Official Government Sources
All calculations verified against these authoritative sources
HM Revenue & Customs
Official UK tax authority providing tax rates, allowances, and guidance
Revenue Scotland
Official Scottish tax authority for devolved Scottish income tax rates
Student Loans Company
Official body managing student loans and repayment thresholds
Office for National Statistics
UK national statistics including inflation rates and economic data
Questions About Compliance?
If you have questions about our data sources, calculation methods, or compliance standards, reach out.