If you’ve ever found yourself thinking, “can I change my year-end date?” This blog is for you. For many UK business owners, the standard company year-end just doesn’t align with how their business operates or cash flow cycles. The good news? You’re allowed to change it. But as with most things in business accounting, there’s a right way to go about it - and a few things to watch out for.

We’ll walk you through everything you need to know about how and why to change your year-end date, whether it makes sense to shorten or lengthen your financial year, and what impact that might have on your taxes and reporting deadlines.

1. First Things First - What Is a Company Year-End?

Before we get into the details, let’s clarify what we mean by “year-end.” Your company year-end, also known as your accounting reference date, is the date that marks the end of your business’s financial year. It determines when you need to submit your annual accounts to Companies House and your Corporation Tax return to HMRC.

When you first register your company with Companies House, your year-end is automatically set as the last day of the month you incorporated. For example, if you registered on 10 July 2023, your year-end would default to 31 July.

But this date isn’t set in stone. That’s where the option to change your year-end date comes in.

2. Reasons You Might Want to Change Your Year-End Date

Now onto the juicy part - why bother changing your year-end date in the first place? Turns out, there are several smart reasons you might want to either shorten or extend it.

1. To Align With the Tax Year

Some companies prefer to match their year-end with the UK tax year (5 April or 31 March), making it easier to line up business accounts with personal tax returns or group companies.

2. To Help with Seasonal Cash Flow

If your busiest (or quietest) time of year lands near your current year-end, changing the date can make managing finances and reporting less stressful.

3. To Prepare for a Sale, Investment, or Merger

If you’re planning to sell your business, bring in investors, or merge with another company, aligning year-end dates can simplify the due diligence process.

4. To Join a Group Structure

When forming or joining a group of companies, aligning year-ends makes consolidated reporting easier and often required for group relief purposes.

5. To Shorten an Extended Period

Perhaps your first year of trading was longer than usual. In this case, you might want to shorten it for tidier year-on-year comparisons or tax planning.

If any of these scenarios apply to you, it might be time to ask: “Should I change my year-end date?” And if so, how?

3. How to Change Your Year-End Date (Step-by-Step)

Thankfully, the actual process of changing your year-end date is fairly straightforward—but there are some rules to follow.

Step 1: Decide on Your New Year-End

Choose the date that works best for your business, considering cash flow, tax planning, and operational alignment. Remember: you can only change your year-end once every 5 years unless you have special permission or you’re doing it to align with a parent company.

Step 2: Notify Companies House

You can change your company’s accounting reference date online via the Companies House WebFiling service, or by sending Form AA01 by post.

What you’ll need:

• Your company number
  

• Authentication code (for online filing)
  

• The new accounting reference date
  

Step 3: Update Your Accounting Systems

Once the change is confirmed, make sure your accounting software reflects the new financial year. This will affect everything from bookkeeping and payroll to budgeting and cash flow projections.

Step 4: Inform Your Accountant or Tax Adviser

If you work with an accountant (which we highly recommend), you should speak to them before you even consider changing your accounting reference date. They’ll help you understand how the change affects your Corporation Tax, filing deadlines, and any reliefs or adjustments.

4. Tax & Reporting Implications to Consider

Changing your year-end date doesn’t just affect your calendar - it impacts your deadlines, taxes, and possibly the length of your accounting periods.

HMRC Rules

You still need to submit a Corporation Tax return for every accounting period, and HMRC won’t accept a period longer than 12 months. So if you extend your year-end beyond that, you’ll need to file two separate tax returns.

For example:

• If you extend your year-end from 31 March 2024 to 30 June 2024, you’ll need one return for the first 12 months (1 April 2023 to 31 March 2024) and another for the extra 3 months (1 April 2024 to 30 June 2024).

Deadline Shifts

Your statutory accounts and Corporation Tax deadlines will shift based on the new year-end. Make sure you diarise the new dates or set up reminders to avoid penalties.

Impact on Allowances

Some reliefs and allowances are time-sensitive. Changing your year-end could influence how much you can claim in a given period (especially for things like the Annual Investment Allowance or R&D tax credits), so plan accordingly.

5. Pros and Cons of Changing Your Year-End

Pros

• Flexibility to align with business or personal goals
  

• Better cash flow timing
  

• Streamlined group reporting
  

• Easier planning for sales or investment

Cons

• May require dual filings if extended beyond 12 months
  

• Can confuse systems or accounting teams if poorly managed
  

• Limited to one change every five years unless exceptional circumstances apply

Final Thoughts: Should I Change My Year-End Date?

If you’ve ever wondered, “Should I change my year-end date to make things easier?” - the answer is, it depends. For some businesses, it’s a strategic move that saves time, aligns better with operations, and offers tax advantages. For others, it may be more hassle than it’s worth.

But one thing’s for sure - making the change for the right reasons and doing it properly is key. Don’t just pick a random date or do it for the sake of it. Think about your business goals, talk to your accountant, and plan ahead.

If you’re not sure whether a change would benefit you, or if you want help filing the paperwork and understanding the tax impact, we’re here to help.

👉 Book a free consultation with our team of expert accountants today and let’s review your company year-end strategy together.