How to Find Your Company's Accounting Reference Date

Your company's accounting reference date (ARD) is one of the most important dates on its Companies House record. It determines when the company's financial year ends and helps establish when its annual accounts must be filed. Yet many new directors are unsure where to find it, how it is calculated, or whether it is the same as their Corporation Tax year-end. The good news is that finding your company's accounting reference date is straightforward.

For most UK companies, the quickest method is to search for the company on Companies House's Find and update company information service and check its filing information. If the company has not changed its accounting reference date, you can also work it out from the incorporation date: for a new company, the first ARD is normally the last day of the month in which the anniversary of incorporation falls. Subsequent ARDs normally fall on the same date each year. Understanding the date matters because an incorrect assumption about your ARD can lead to missed accounts deadlines, late filing penalties and confusion about your tax reporting obligations.

What Is an Accounting Reference Date?

An accounting reference date is the date on which a company's accounting reference period normally ends. In simpler terms, it is your company's financial year-end for Companies House purposes.

For an existing company, the next financial year normally starts on the day after the previous financial year ended. For a newly incorporated company, the first financial year begins on the date the company is incorporated. For most newly incorporated companies, Companies House automatically establishes the first ARD based on the incorporation date. For example:

After the first year, subsequent accounting reference dates normally fall on the same date each year.

The Easiest Way to Find Your Company's Accounting Reference Date

The most reliable approach is to check your company's record directly with Companies House.

Step 1: Search for your company

Go to the Companies House Find and update company information service and search using your:

• company name
• company registration number

Using the company registration number is usually the safest option because company names can be similar.

Step 2: Open the correct company record

Check that the record belongs to your company. Pay particular attention to the:

• company name
• company number
• registered office
• company status

This is especially important if you are searching by name rather than registration number.

Step 3: Look at the filing information

Your Companies House record contains information about your accounts and filing history. The company's accounts information will show the relevant accounting period and filing dates. Companies House also confirms that companies can check their new accounting reference date through its company information service after an ARD has been changed.

This is preferable to relying on an old letter, spreadsheet or accountant's calendar. The Companies House record should be your starting point when checking the current ARD.

Can You Calculate Your Accounting Reference Date Yourself?

Yes, if the company has never changed its accounting reference date. For a new company, the rule is relatively simple: The first accounting reference date is normally the last day of the month in which the anniversary of incorporation falls.

Companies House gives the example of a company incorporated on 6 April 2025. Its first accounting reference date is 30 April 2026, and subsequent ARDs will normally fall on 30 April each year.

Example 1: Incorporated in February

Suppose your company was incorporated on 12 February 2026. Its normal first ARD would be: 28 February 2027, The following accounting reference date would normally be: 28 February 2028

Example 2: Incorporated in September

Suppose your company was incorporated on 17 September 2026. Its first ARD would normally be: 30 September 2027, After that, the ARD would normally remain 30 September each year.

Example 3: Incorporated in December

A company incorporated on 4 December 2026 would normally have its first ARD on: 31 December 2027, Its subsequent ARDs would normally fall on 31 December. The key point is that the calculation uses the month of the incorporation anniversary, then takes the last day of that month.

Why Your First Accounting Reference Date Matters

The ARD does more than identify your financial year-end. It determines the end of your company's accounting reference period and therefore plays a major role in calculating when your annual accounts must be filed. For a private company, subsequent annual accounts are normally due 9 months after the end of the accounting reference period. Public companies generally have 6 months. The first accounts are subject to different rules.

A new company's first accounting period begins on incorporation and normally ends at its first ARD. This means the first accounts commonly cover more than 12 months. GOV.UK gives the example of a company incorporated on 11 May having an ARD of 31 May the following year, producing a first accounting period of approximately 12 months and three weeks. This is why simply saying "my accounts are due nine months after my year-end" can be misleading when dealing with a company's first accounts.

Is the Accounting Reference Date the Same as the Company Tax Year-End?

Not necessarily. This is one of the most important distinctions for company directors. Your Companies House accounting reference date relates to your company's statutory accounts. Your Corporation Tax accounting period is an HMRC concept and follows different rules. A new company can therefore have:

• a Companies House accounting reference date;
• a Companies House accounts filing deadline;
• a Corporation Tax accounting period; and
• a Company Tax Return deadline.

These dates can overlap without being identical. GOV.UK specifically warns that when a company is set up, it automatically receives different reporting dates for its first annual accounts and Company Tax Return. A company may even need to submit two tax returns covering its first period of business.

A practical example

Imagine a company incorporated on 11 May 2026. Its normal first ARD is: 31 May 2027, Its first Companies House accounts therefore cover more than 12 months. But that does not mean its Corporation Tax accounting period can simply run for those same 12 months and three weeks. Corporation Tax accounting periods cannot exceed 12 months. For a founder, this distinction is critical. Companies House deadline ≠ Corporation Tax deadline.

What If Your Company Has Changed Its Accounting Reference Date?

This is where calculating the ARD from the incorporation date can become unreliable. A company can change its accounting reference date for its current or immediately previous accounting period. The change can shorten or lengthen the financial year, subject to Companies House rules.

Once an ARD has been changed, the date shown in your current Companies House record is more important than the date you calculate from the original incorporation date. For example, suppose:

• Company incorporated: 10 March 2025
• Original ARD: 31 March
• Company later changes its year-end to 30 September

You should not continue calculating the company's filing dates from the original March ARD. The company now has a different accounting timetable. This is why checking the live Companies House record is the safest method.

How to Tell If Your Accounting Reference Date Has Changed

There are several clues.

Check the accounts filing history

Look at the company's filing history and compare the accounting periods shown for different sets of accounts. A sudden change in the year-end can indicate that the ARD has been altered.

Check for an AA01 filing

An AA01 is the Companies House form used to change a company's accounting reference date. Companies can also make the change online or using compatible software. If an AA01 has been filed, do not assume the original incorporation-based ARD still applies.

Check with whoever manages the company's accounts

If an accountant or company secretarial provider handles your compliance, ask them to confirm the current ARD and the corresponding accounts deadline. This is particularly useful where the company has previously changed its financial year-end.

Can You Change Your Company's Accounting Reference Date?

Yes. Companies House allows a company to change its financial year-end, also known as its accounting reference date. You can generally:

• shorten the financial year as often as permitted;
• lengthen it subject to statutory restrictions;
• change the current or immediately previous accounting period.

A company can generally lengthen its financial year to a maximum of 18 months, and normally can only do so once every five years. Exceptions can apply, including certain situations involving a parent or subsidiary relationship, administration or permission from Companies House. The important point is that changing your year-end is not simply an administrative preference. It can affect your filing timetable and your Corporation Tax accounting period.

When Is It Too Late to Change the ARD?

Timing matters. Companies House states that you cannot change your accounting reference date when the company's accounts are already overdue. The change must be made within the period allowed for delivering the relevant accounts. This creates an important practical rule: Do not wait until your accounts are overdue before deciding that your year-end needs changing.

If the accounts have already become overdue, changing the ARD will not provide a way around the late filing consequences. If you have already received an extension to your filing deadline, changing the ARD can also affect that extension.

Can You Choose Any Date for Your Financial Year-End?

Not quite. A company has flexibility to change its accounting reference date, but the resulting accounting period must comply with the statutory rules. Companies House states that a company can make its accounts up to the ARD or a date up to seven days either side of it.

That flexibility can be useful for accounting purposes, but it does not mean directors can arbitrarily choose any date and treat it as their official ARD. If you want to formally change the year-end, the proper Companies House process should be followed.

Why Might a Company Change Its Accounting Reference Date?

For some businesses, the default year-end is perfectly suitable. Others may have commercial reasons to change it.

Group reporting

A UK subsidiary may want its financial year to align with its overseas parent company.

Seasonal businesses

A retailer may prefer a year-end after its busiest trading period rather than during it.

International founders

A founder operating businesses across several countries may want reporting periods that make group consolidation easier.

Internal management

A growing business may find a particular month more convenient for budgeting, audits, stock counts or investor reporting. However, convenience should not be the only consideration. Changing the year-end can affect accounting workloads, tax reporting and the timing of statutory filings.

Common Mistakes When Checking an ARD

Mistake 1: Confusing incorporation date with accounting reference date

If your company was incorporated on 15 June, the ARD is not normally 15 June the following year. It will normally be 30 June.

Mistake 2: Assuming the original ARD is permanent

A company can change its accounting reference date. Always check the current Companies House information.

Mistake 3: Confusing ARD with Corporation Tax year-end

They are related concepts but operate under different rules.

Mistake 4: Looking only at the accounts filing deadline

The filing deadline tells you when accounts must reach Companies House, but it is not itself the ARD.

Mistake 5: Relying on an old accountant's calendar

If the company has changed accountants or changed its year-end, an old calendar may no longer be accurate.

A Simple ARD Checking Routine for Directors

You do not need a complicated system. Once or twice a year, check:

1. Company number — confirm you are looking at the correct entity.
2. Current accounting reference date — check the Companies House record.
3. Last accounts period — confirm the period that was filed.
4. Next accounts deadline — make sure the filing date is diarised.
5. ARD changes — check whether an AA01 or online change has been submitted.
6. HMRC dates — separately confirm Corporation Tax accounting periods and tax deadlines.

This becomes especially important for founders who operate several UK companies. Each company has its own compliance timetable, even if the same director controls all of them.

Why the ARD Matters to Global Founders

For an overseas entrepreneur establishing a UK company, the accounting reference date can easily be overlooked. The company may have:

• a UK registered office;
• directors living abroad;
• international shareholders;
• overseas customers;
• a foreign parent company; or
• an accountant in another country.

None of those circumstances removes the company's UK Companies House filing obligations. For global founders using IncorpUK, a UK company formation and management platform for global founders, the ARD is one of the basic dates worth recording alongside the company's incorporation date, confirmation statement deadline and tax obligations. The broader lesson is that incorporating a UK company creates an ongoing compliance calendar, not just a registration record.

Frequently Asked Questions

How do I find my company's accounting reference date?

Search for your company using the Companies House Find and update company information service. Your accounts and filing information can be used to identify the company's accounting period and current reporting timetable.

What is the accounting reference date for a new company?

For a new company, the first ARD is normally the last day of the month in which the anniversary of incorporation falls. Subsequent ARDs normally fall on the same date each year.

Is my accounting reference date the same as my company's year-end?

For Companies House purposes, the ARD is effectively the date used to determine the end of the company's financial year. However, a company can prepare its accounts to a date up to seven days either side of the ARD.

Can I change my accounting reference date?

Yes. A company can change its current or immediately previous accounting reference date, subject to Companies House rules concerning timing and the length of the resulting accounting period.

How often can I extend my company's financial year?

A company can normally lengthen its financial year only once every five years, and the resulting period cannot normally exceed 18 months. Exceptions can apply in particular circumstances.

Can I change my ARD if my accounts are already overdue?

No. Companies House states that a company's accounting reference date cannot be changed when its accounts are overdue.

Does changing my ARD affect Corporation Tax?

It normally can. GOV.UK states that changing the company's year-end will normally affect its Corporation Tax accounting period, so the relevant dates with HMRC may also need to be updated.

Is the accounting reference date shown on Companies House?

Yes. Companies House provides company information and filing records that allow you to check the company's current accounting timetable. If an ARD has been changed, Companies House specifically advises checking the company's information online to see the new date.

Conclusion

Finding your company's accounting reference date is usually straightforward, but knowing which date to trust is just as important as knowing how to calculate it. For a newly incorporated company that has never changed its year-end, the first ARD is normally the last day of the month in which the incorporation anniversary falls. After that, the ARD normally repeats annually.

But if the company has changed its accounting reference date, do not rely on the original incorporation date. Check the current Companies House record and filing history instead. Most importantly, keep the ARD separate from your Companies House filing deadline and Corporation Tax deadlines. They are connected, but they are not interchangeable.

For a new UK company, knowing the ARD gives you a reliable starting point for building the wider compliance calendar and helps ensure that annual accounts, tax returns and other statutory obligations are dealt with before they become urgent.