Working with CASS

What it costs and what moves the price, how switching works, onboarding and the first 90 days, and who does the work.

These answers provide general information, not advice tailored to your circumstances. Rules can change and exceptions may apply — speak to the CASS team before making a tax, accounting or financial decision.

Often, yes. We assess whether we can support your business based on its circumstances, complexity and the work required. Groups bring intercompany balances, consolidation questions and more than one filing timetable, so we look at the structure and what is actually needed before confirming what we can take on and what would need a specialist.

Last updated 2 October 2026

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