Running a company in Ireland comes with important legal and tax obligations. One of the most common challenges business owners face is keeping track of filing deadlines. Missing these deadlines can lead to penalties, unnecessary stress, and even the loss of valuable exemptions.

Two of the most important obligations every company director should understand are:

• CRO Annual Returns (your statutory company filing)
• Corporation Tax Returns (your Revenue tax filing)

Even if you don’t have an accounting background, understanding the basics can help you stay compliant and avoid costly mistakes.

1. CRO Filing Deadlines (Annual Return Date – ARD)

Every Irish company is required to submit an annual return to the Companies Registration Office (CRO). This filing is commonly known as a B1 Annual Return and is separate from your corporation tax return.

Your company will have an Annual Return Date (ARD), and once that date arrives, you generally have 56 days to file your return.

First CRO Return

Your first annual return is due:

• 6 months after incorporation
• No financial statements are required at this stage
• The filing mainly confirms basic company details

This is usually a straightforward administrative filing.

Second CRO Return

Your second annual return is due:

• 12 months after the first ARD
• Financial statements must now be included
• This requirement continues annually thereafter

This is often the point where companies begin working closely with an accountant.

2. Corporation Tax Deadlines (Revenue Filing)

In addition to CRO obligations, companies must also file a Corporation Tax Return (CT1) with Revenue.

The CT1 filing deadline is:

• 8 months and 23 days after your financial year-end

Any corporation tax owed must also be paid by this deadline.

Choosing Your Financial Year-End

Companies can choose their own financial year-end, which is usually the last day of a month.

Many businesses choose:

• 31 December to align with the calendar year
• A quieter trading period to simplify bookkeeping and reporting

Example

If your company’s year-end is:

• 31 December 2026

Then your:

• CT1 filing and tax payment deadline will be 23 September 2027.

Important Things to Keep in Mind

Your Accounts May Be Needed Earlier

Although your CT1 deadline may fall later, your accounts often need to be prepared sooner because they are required for your second CRO annual return.

For many new companies:

• First accounts are typically required within 18 months of incorporation.

Preliminary Tax

Companies may also need to pay preliminary tax during the year.

Small Companies

• Pay preliminary tax in a single payment
• Due 1 month before year-end

Large Companies

• Pay preliminary tax in two instalments

First-Year Companies

• Usually no preliminary tax is required in the first year.

How Filing Deadlines Work in Practice

Example 1: Company with a 31 December Year-End

In practice, many businesses prepare their accounts by July and file both CRO and tax returns together.

Example 2: Company with a Non-December Year-End

Even though the CT1 deadline is later, many companies still complete everything earlier because their accounts are already prepared for the CRO filing.

Accounting Periods: Understanding the Flexibility

Companies are not strictly limited to 12-month accounting periods.

Some important rules include:

• First accounts can cover up to 18 months from incorporation
• Future financial years cannot exceed 18 months
• Changing your year-end may create shorter or longer accounting periods
• Updating your year-end may also require changes to your ARD

What Happens If You Miss CRO Deadlines?

Late CRO filings can lead to serious consequences, including:

• Loss of audit exemption after repeated late filings
• Late filing penalties:
  • €100 initial penalty
  • Plus €3 per day thereafter
• Risk of company strike-off

For small businesses, losing audit exemption can significantly increase accounting costs.

How New Companies Can Stay Organised

To avoid filing issues and last-minute pressure, it’s important to stay proactive.

Practical Tips

• Note your ARD immediately after incorporation
• File your first annual return on time
• Engage an accountant before your second ARD
• Set up a reliable bookkeeping system early

While your first accounts may not be due for up to 18 months, leaving everything until the final weeks can create unnecessary stress and complications.

How Accountants4SME Can Help

At Accountants4SME, we support Irish limited companies with:

• Bookkeeping and payroll services
• Tax planning and advisory
• CRO Annual Return (B1) filings
• Corporation Tax Return (CT1) submissions
• Director’s Form 11 preparation

We provide clear, fixed-fee pricing and practical support tailored to your business needs.

Whether you’re launching a new company or considering switching accountants, the process is straightforward and can be done at any time during the year.

Get in touch with Accountants4SME today to arrange an initial consultation and ensure your company stays compliant and stress-free.