Ten Tenets for a Better Tax System

The tax system should be:

1. Statutory. Tax legislation should be enacted by statute and subject to proper democratic scrutiny by Parliament. A clear statutory basis ensures legitimacy, accountability, and public trust in the tax system. 
2. Certain. As far as possible, the application of tax rules and compliance processes should be certain. Taxpayers should not normally need to resort to the courts to understand how the rules apply to their affairs.
3. Simple. The tax system should be easy to understand for all taxpayers and advisers. Complexity undermines trust, creates unfairness, and discourages compliance.
4. Easy to administer. Tax liabilities should be straightforward to administer for HMRC, agents, and all taxpayers. Taxes should be designed to work effectively in a digital environment, while administration must remain accessible to those with limited digital capability.
5. Properly targeted. Anti-avoidance rules and other targeted measures should be proportionate, clearly defined, and carefully scoped to achieve their policy objective without undermining simplicity or certainty. Poorly targeted measures add complexity and uncertainty, harming compliance.
6. Stable. Changes to the tax system should only be made when clearly justified by economic, social, or environmental goals. Transparent, purposeful reforms build confidence and move the system toward greater coherence and long-term stability.
7. Subject to proper consultation. Other than in exceptional circumstances, tax changes should be subject to open and meaningful consultation. Adequate time for stakeholder input improves policy quality, practicality, and public trust.
8. Regularly reviewed. Tax rules, reliefs, and policy-driven interventions should be subject to regular, transparent review to assess whether they remain relevant, effective, and aligned with current policy goals. Outdated or unjustified provisions should be reformed or repealed to maintain coherence.
9. Fair and accessible. The tax system should be fair and accessible in design and in operation, ensuring equitable treatment of taxpayers. Revenue authorities must exercise their powers proportionately, and all taxpayers should have timely access to HMRC assistance, independent appeal, and redress.
10. Efficient. The tax system should raise revenue in a way that minimises unnecessary distortions, compliance burdens, and resource misallocation. While all taxes affect behaviour to some degree, tax design should avoid cliff edges, unintended incentives, or inefficiencies that reduce economic wellbeing unless these serve a clearly defined policy aim.

ICAEW first published its Ten Tenets for a Better Tax System in October 1999. The Tenets were revised in April 2026. The article ICAEW's ten tenets: why we are changing them explains what changes were made and why.