Guides
Guides in plain English to associated companies, groups and close companies. Each one has the checker built in.
Associated companies
Are a spouse's or relative's companies associated?
When family members' companies count as associated for corporation tax, which relatives count, and what HMRC means by substantial commercial interdependence.
Do dormant companies count as associated companies?
When a dormant company, or one that doesn't trade, is left out of the associated companies count, why Companies House dormant accounts aren't the whole answer, and how holding companies are treated.
HMRC has written about associated companies: what to do
Why HMRC sent the letter, how to check the associated companies count on each return since April 2023, and how to correct or explain it.