How to Check Companies House Filing Deadlines in Bulk

Checking Companies House filing deadlines for a handful of clients is straightforward. Checking them for 30, 50, or 80 clients reliably — every week, without missing anyone — is a different problem. And if you're also tracking VAT quarters, CT deadlines, payroll dates, and compliance renewals, the problem multiplies fast. This article explains why manual approaches break down at scale and what a practical bulk-monitoring workflow looks like.

Why manual checking fails at scale

There are two distinct Companies House deadlines for every active limited company: the annual accounts due date and the confirmation statement due date. Each company has different dates for each. A practice with 40 LTD clients may have 80 separate deadlines spread unevenly across the year.

The failure modes of manual checking are predictable:

• Spreadsheet drift. When a client files early or changes their accounting reference date, the due date in the Companies House register changes. A spreadsheet only reflects this change if someone manually updates it — and that update is often missed.
• Attention gaps. Spreadsheets require someone to actively look at them. During a busy period (January self-assessment season, year-end crunch), deadline reviews get deferred, and companies slip through.
• No early warning. Even a well-maintained spreadsheet tells you a deadline is approaching only if you look at it frequently enough. It does not send you an alert 30 days in advance without additional automation.
• New clients not added. When a new client is onboarded, adding them to the monitoring spreadsheet is a manual step that can be forgotten in a busy practice.

Limitations of the Companies House website for bulk checks

The Companies House website (find-and-update.company-information.service.gov.uk) is the authoritative source for filing status and due dates. It is excellent for looking up individual companies. It is not designed for portfolio-level monitoring.

Specifically:

• There is no dashboard or export showing all upcoming deadlines for a list of company numbers.
• You cannot set up custom advance alerts (the built-in reminder emails are sent close to the due date, not 30 days ahead).
• There is no bulk lookup — you must search one company at a time.
• There is no API access through the website UI itself; the public API requires a free API key and development effort to use directly.

Companies House does offer a free email reminder service for individual companies, but it sends a single reminder close to the due date — not a configurable advance warning — and requires you to register each company separately. We weigh the trade-offs of every option in free and paid Companies House reminder tools.

Using a monitoring tool: what to look for

A dedicated monitoring tool solves the bulk-checking problem by reading the public API automatically — daily, for every company in your list — and alerting you when deadlines are approaching. When evaluating a tool, the key questions are:

• Does it read directly from Companies House? The authoritative source is the CH public API. Tools that cache data infrequently or rely on secondary sources may show outdated due dates.
• Does it cover HMRC and compliance obligations? CH deadlines are only part of the picture. Look for tools that also track VAT quarters, Corporation Tax, payroll (RTI, P11D, CIS), pension auto-enrolment, and regulatory renewals (ICO, MLR) — per client, not just firm-wide.
• How far in advance are alerts sent? 30 days is the minimum useful lead time for accounts — you need enough runway to chase clients for records. 7 days is a useful final reminder.
• How do you add companies? Adding one company at a time is fine for small portfolios. For larger practices, CSV import (paste or upload a list of company numbers) saves significant setup time.
• What data does it access? A responsible tool reads only the public Companies House register for CH deadlines and stores only the HMRC/compliance dates you supply — no accounting software integration or client financial data is required.
• What is the pricing model? Per-company pricing can become expensive at scale. Per-practice flat-rate pricing (unlimited or high-cap companies for a fixed monthly fee) is more predictable for a growing portfolio.

How PenaltyProof handles bulk monitoring

PenaltyProof is built specifically for this use case. You add company numbers — either one at a time or by pasting a list — and it monitors them automatically using the Companies House public API for CH deadlines. For each company you can also configure HMRC and compliance obligations: VAT stagger group, CT period end, payroll settings, pension staging dates, ICO renewals, and more. Every day it checks and evaluates all configured deadlines. On paid plans, alerts are sent 30 days, 14 days, and 7 days before each deadline, on the day it falls, and again once it goes overdue.

There is no spreadsheet to maintain. If a client files early and their next CH due date shifts, PenaltyProof picks that up at the next daily check without any action on your part. HMRC and compliance dates that you configure stay fixed until you update them.

The free tier supports up to 5 companies — enough to verify the workflow before committing. For practices monitoring more clients:

• Starter plan (£29/month, or £290/year): up to 50 companies, with advance alerts at 30 days, 14 days, and 7 days before each deadline
• Pro plan (£39/month, or £390/year): unlimited companies, same alert cadence as Starter

Adding 10 or more clients by CSV

If you have a list of company numbers in a spreadsheet, you can paste them directly into the CSV import field in PenaltyProof. The format is one company number per line (or comma-separated). The service looks up each number against the Companies House API to confirm it exists and retrieve the company name, then adds all valid companies to your monitoring list in a single operation.

This makes onboarding a full client portfolio a matter of minutes rather than hours.

Recommended workflow for bulk monitoring

Once your client list is set up in a monitoring tool with advance alerts, a sensible ongoing workflow is:

1. Let the 30-day alert prompt client outreach. When a 30-day alert arrives, contact the client to confirm records are in order (for accounts) or that the information on the register is still accurate (for a confirmation statement).
2. Use the 14-day alert as a check-in. A short follow-up between the first nudge and the final push — useful for catching clients who said they would send records but haven't.
3. Use the 7-day alert as a hard deadline trigger. If you have not heard back from a client by the 7-day alert, escalate. For annual accounts, this may mean filing an extension application to Companies House — see how Companies House late filing penalties work for what's at stake. For a confirmation statement, it means filing it with current information and updating later if needed.
4. Add new clients immediately at onboarding. Build the step "add to monitoring tool" into your new client onboarding checklist so no company is ever unmonitored.
5. Review your list quarterly. Remove any company numbers for clients who have left the practice or had their companies dissolved, so your list stays accurate.