CT600 Deadline: When Is Your Company Tax Return Due?
When is your CT600 due? Your company tax return deadline is 12 months after the accounting period ends. Late filing means automatic penalties.
Plain-English guides to UK Corporation Tax and CT600 filing.
When is your CT600 due? Your company tax return deadline is 12 months after the accounting period ends. Late filing means automatic penalties.
Complete guide to CT600 late filing penalties and charges. How much you'll pay, when penalties apply, and how to appeal HMRC penalty decisions.
Complete checklist of records and documents needed for CT600 filing. How long to keep them, what HMRC expects, and how to organize everything.
HMRC is shutting down its free CT600 filing service in March 2026. Here's what's changing, why it matters, and what your options are going forward.