Quick answer
Accountants track Companies House and HMRC deadlines by taking dates from official records, calculating each deadline from the accounting period, storing them against the client with an internal target date, and reviewing them whenever company details change. Automated client reminders and a monthly deadline review stop late filings.
Written by Waqas Sagar ACA FCCA, Founder of Accotax and Remindoo · Last updated · 5 min read · Part of Companies House and HMRC guides
Why deadlines drift
To track Companies House and HMRC deadlines well you need accurate source data. The usual cause of a late filing is not forgetting; it is a date that was wrong from the start or that changed, such as a shortened year end.
Every company has several dates tied to one accounting period, and each is calculated differently.
The spreadsheet approach
Many firms keep a deadline spreadsheet. It works until a company changes its year end or a new client is added with a typing error. Nothing checks the data against Companies House.
A reliable deadline process
Take company details from Companies House rather than typing them. Calculate accounts, confirmation statement, Corporation Tax payment and CT600 dates from the period end.
Store each deadline on the client with an internal target and an owner. Re-check dates whenever you receive notice of a change, and review everything due in the next 90 days each month.
Send clients reminders well before you need their records, not just before the deadline.
| Obligation | Usual deadline |
|---|---|
| Annual accounts to Companies House | 9 months after period end |
| Corporation Tax payment | 9 months and 1 day after period end |
| CT600 return | 12 months after period end |
| Confirmation statement | Within 14 days of review period end |
Checking the rules
Rules for first accounts, changed year ends and large companies differ. Use GOV.UK or the free Remindoo deadline checker for a quick calculation, then confirm unusual cases on GOV.UK.
How Remindoo solves this
Remindoo syncs company data and filing dates from Companies House, singly or in bulk, and keeps deadlines on each client. Automated reminders ask clients for records in good time. Remindoo manages the work; filing is done in your usual software.
- Companies House Sync
- Bulk Sync
- Manage Deadline
- Automated Reminders
- HMRC Integration
Frequently asked questions
What happens if accounts are filed late?
Companies House charges an automatic late filing penalty that increases with how late the accounts are. Penalties are higher for public companies and double if accounts are late two years running. Check GOV.UK for current amounts.
Is the CT600 due at the same time as the tax payment?
No. For most companies the tax is due nine months and one day after the period end, while the return is due 12 months after it. Paying on time avoids interest even if the return comes later.
How do I check a company's filing dates?
Companies House shows the next accounts and confirmation statement due dates on the company's public record. Practice software that syncs with Companies House can pull these for you.
Can I calculate deadlines for free?
Yes. Remindoo's free Companies House deadline checker calculates accounts, Corporation Tax, CT600 and confirmation statement dates from a year end.
Related guides
All companies house and hmrc guides
Companies House deadline checker
Lost Companies House authentication code
