UK SME Compliance Calendar: HMRC & Companies House Deadlines

The UK SME Compliance Calendar: Key Deadlines for HMRC and Companies House

For SME founders and finance managers, the UK regulatory landscape can feel like a maze. You are not just reporting to one authority, but two: Companies House (the registrar of companies) and HMRC (the tax authority). Each has its own set of deadlines, rules, and penalties.

Confusing a “filing deadline” with a “payment deadline” is a common and costly error. This guide provides a definitive calendar of critical dates, helping you maintain a clean compliance record while avoiding the unnecessary stress of last-minute firefighting.

Companies House Deadlines: Keeping Your Record Clean

Companies House is focused on transparency and corporate governance. Your filings here are public record and missing a deadline not only incurs fines but places a red flag on your credit report, potentially damaging supplier relationships.

1. Filing Your Annual Accounts

Every limited company must prepare annual accounts that report on financial performance.

• The Deadline: For private limited companies, you must file your accounts 9 months after your financial year ends.

• Example: If your year-end is 31 March, your accounts must be filed by 31 December.

• The Risk: Filing late is a criminal offence. Furthermore, credit agencies often downgrade the credit rating of companies that file late, which can impact your ability to secure favourable payment terms from vendors.

2. The Confirmation Statement (Formerly Annual Return)

Unlike annual accounts, which are about money, the Confirmation Statement (form CS01) is about identity. It confirms who the directors, shareholders, and “People with Significant Control” (PSCs) are.

• The Deadline: You must file this at least once a year. The deadline is 14 days after the end of your “review period” (usually the anniversary of incorporation).

• Strategic Tip: Use this opportunity to audit your own governance. Ensure your internal records match the public register. For your supply chain, you should be demanding the same transparency. See our Vendor Compliance Guide for details on vetting your partners.

HMRC Deadlines: Managing Your Tax Liability

HMRC is focused on tax collection. The penalties here can escalate quickly, especially if you underpay.

1. Corporation Tax: The “Payment First” Rule

This is the most common tripping point for new finance managers.

• Payment Deadline: You must pay your Corporation Tax 9 months and 1 day after your accounting period ends.

• Filing Deadline: You must file your Company Tax Return (CT600) 12 months after your accounting period ends.

The Trap: You must pay the tax before the deadline to file the return. If you wait until the filing deadline to check what you owe, you will already be three months late on payment, accruing interest.

2. VAT Returns (Making Tax Digital)

Most SMEs submit VAT returns quarterly.

• The Deadline: usually 1 calendar month and 7 days after the end of your VAT period.

• Requirement: Under Making Tax Digital (MTD), you must keep digital records. Manual typing of figures into the HMRC portal is no longer compliant for most steps; data must flow digitally.

3. PAYE and National Insurance

If you have employees, you act as an unpaid tax collector for the government.

• The Deadline: You must pay PAYE and Class 1 National Insurance to HMRC by the 22nd of the next tax month (if paying electronically).

The Cost of Missing Deadlines (Penalties Snapshot)

The financial impact of disorganization can be severe. Here is a snapshot of the immediate penalties for private limited companies.

Violation	Time Overdue	Penalty
Late Accounts (Companies House)	Up to 1 month	£150
	1 to 3 months	£375
	3 to 6 months	£750
	More than 6 months	£1,500
Late Tax Return (HMRC)	1 day late	£100
	3 months late	Another £100
	6 months late	HMRC estimates your tax bill + 10% penalty

Note: If you file your accounts late two years in a row, the penalties are doubled.

Why “Just in Time” Compliance is Risky

Many SMEs treat compliance as a “once-a-year” event, leading to a frantic scramble in the final weeks. This approach carries significant risks:

• Lost Documentation: Trying to find a contract or invoice from 11 months ago is difficult.

• Overpaid Tax: If you cannot find a valid receipt for an expense, you cannot deduct it from your profits, meaning you pay more Corporation Tax than necessary.

• Data Accuracy: Rushed data entry leads to errors in your statutory reporting.

How Vendorfi Ensures You Are Deadline-Ready

The secret to stress-free compliance is moving from a “yearly panic” to “continuous readiness.” Vendorfi supports this shift by organizing your financial data upstream.

Audit-Ready Vendor Data

Instead of chasing suppliers for VAT numbers or invoices at year-end, Vendorfi captures this data during the onboarding process. By strictly following a vendor onboarding checklist, you ensure that every supplier in your system is compliant from day one.

Centralized Documentation

Auditors and tax inspectors require proof. Vendorfi acts as a secure repository for all your vendor contracts and compliance documents. When the deadline approaches, you don’t need to dig through emails as the data is already organized.

Proactive Risk Management

Compliance isn’t just about filing dates, it’s about knowing who you are paying. Vendorfi helps you maintain a robust vendor risk management framework, ensuring that you aren’t doing business with entities that could jeopardize your own standing with regulators.

Conclusion

Deadlines are inevitable, but the stress associated with them is not. By understanding the distinction between Companies House and HMRC requirements, and by leveraging tools like Vendorfi to maintain a state of continuous compliance, you can turn these regulatory hurdles into routine administrative tasks.

Mark your calendar, automate your data collection, and face the financial year-end with confidence.

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Frequently Asked Questions (FAQ)

What happens if I miss the Companies House deadline?

You will automatically receive a penalty notice. If you ignore this and fail to file for a significant period, the Registrar may assume the company is no longer trading and take steps to strike it off the register, freezing your bank accounts.

Can I extend my filing deadline?

You can apply for an extension with Companies House if you are prevented from filing by an event outside your control (e.g., a fire or serious illness). You must apply before the filing deadline.

Do I have to file if my company is dormant?

Yes. Even if your company has not traded, you must still file “Dormant Accounts” and a Confirmation Statement every year to keep the company on the register.