When is the Form 1120 filing deadline for a US C-Corp in 2026?

For C-Corporations operating on a calendar year, the 2026 deadline to file Form 1120 is April 15, 2026. If your business operates on a fiscal year ending June 30, the deadline is September 15, 2026. You may request a six month extension by filing Form 7004, which moves the filing date to October 15, 2026, though all taxes owed must still be paid by the original April date.

What is the 2026 HMRC deadline for paying UK Corporation Tax?

UK companies must pay their Corporation Tax liability 9 months and 1 day after the end of their accounting period. For a company with a financial year ending December 31, 2025, the payment is due by October 1, 2026. This deadline is distinct from the CT600 filing deadline, which is typically 12 months after the end of the accounting period, meaning December 31, 2026, for calendar year businesses.

Can a Canadian corporation file its 2026 T2 return more than six months after year end?

No, the legal deadline for a Canadian corporation to file its T2 Corporation Income Tax Return is exactly six months after the end of its fiscal year. Small businesses with a December 31 year end must file by June 30, 2026. However, if the corporation owes taxes, the balance of tax must generally be paid within 2 or 3 months after year end to avoid interest charges.

When must a UAE company file its first Corporate Tax return in 2026?

In 2026, UAE companies must file their Corporate Tax return within 9 months from the end of the relevant Tax Period. For businesses that adopted a fiscal year starting June 1, 2025 and ending May 31, 2026, the return and payment must be submitted to the Federal Tax Authority by February 28, 2027. Businesses with a calendar year ending December 31, 2025 must file their first return by September 30, 2026.

2026 Corporate Tax Deadlines: US, UK, Canada, and UAE Guide…

In 2026, corporate tax filing deadlines vary significantly by jurisdiction: US C-Corps must file Form 1120 by April 15, UK companies must file Form CT600 within 12 months of their year end, Canadian T2 returns are due 6 months after year end, and UAE entities must file within 9 months of their fiscal close. Missing these dates can trigger substantial penalties, interest, and loss of good standing status.

Navigating Corporate Tax Deadlines in 2026

Staying compliant with international tax regimes requires a high degree of precision. This guide covers the specific 2026 corporate tax filing requirements and deadlines for the four major jurisdictions served by Gullia Filing: the United States, United Kingdom, Canada, and the United Arab Emirates. You will learn the specific form names, payment timelines, and statutory dates necessary to maintain your tax and accounting compliance across borders.

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When is the 2026 US Corporate Tax Deadline?

For US C-Corporations, the 2026 filing deadline for Form 1120 is the 15th day of the fourth month following the close of the tax year. For businesses operating on a standard calendar year (ending December 31), the deadline is April 15, 2026. If your corporation is a fiscal year filer, you must calculate four months from your specific end date.

It is vital to distinguish between the filing deadline and the payment deadline. The IRS requires that all estimated taxes be paid throughout the year, with the final balance due by the original filing date, regardless of whether an extension is filed. If you file Form 7004 to request an extension, your new filing deadline becomes October 15, 2026. S-Corporations and Partnerships typically have an earlier deadline of March 16, 2026 (since the 15th falls on a Sunday).

What are the 2026 UK Corporation Tax Filing Rules?

The UK system separates the deadline for paying tax from the deadline for filing the return. In 2026, companies must pay their Corporation Tax within 9 months and 1 day after the end of their accounting period. For a company with an accounting period ending December 31, 2025, the tax payment is due on October 1, 2026.

However, the actual UK Corporation Tax return (Form CT600) is not due until 12 months after the end of the accounting period. For that same calendar year company, the filing deadline is December 31, 2026. Failure to file on time results in an immediate 100 GBP penalty, which increases to 200 GBP if the return is more than three months late.

How are Canadian T2 Return Deadlines Calculated in 2026?

Canadian corporations must file their T2 Corporation Income Tax Return within six months of the end of each tax year. For a fiscal year ending December 31, 2025, the filing deadline is June 30, 2026. If the end of the tax year falls on the last day of a month, the return is due on the last day of the sixth month following.

Country	Primary Form	Filing Deadline	Payment Deadline
USA	Form 1120	4 Months Post Year-End	4 Months Post Year-End
UK	Form CT600	12 Months Post Year-End	9 Months + 1 Day Post Year-End
Canada	Form T2	6 Months Post Year-End	2 to 3 Months Post Year-End
UAE	Tax Return	9 Months Post Year-End	9 Months Post Year-End

In Canada, the payment deadline is often earlier than the filing deadline. Most corporations must pay their taxes owing within two months after the end of the tax year. However, certain Canadian Controlled Private Corporations (CCPCs) may be eligible for a three month payment window if they meet specific income thresholds.

London office space for financial services

What are the UAE Corporate Tax Filing Deadlines in 2026?

The UAE Corporate Tax regime, governed by the Federal Tax Authority (FTA), requires all taxable persons to file a tax return and pay the due tax within 9 months from the end of the relevant Tax Period. For many companies, 2026 marks the first full year of compliance.

If your UAE Free Zone or Mainland entity operates on a calendar year ending December 31, 2025, your deadline to file and pay is September 30, 2026. Businesses must ensure they are registered for Corporate Tax before these deadlines occur. The UAE does not currently offer an extension for the 9 month filing window, making timely data collection essential.

Key Compliance Dates Checklist for 2026

To ensure your business avoids penalties, follow this 2026 compliance roadmap:

January 15, 2026: Fourth quarter 2025 estimated tax payment due for US corporations.
March 16, 2026: Filing deadline for US S-Corps and Partnerships (Form 1120-S / 1065).
April 15, 2026: Filing and payment deadline for US C-Corps (Form 1120).
June 30, 2026: T2 filing deadline for Canadian corporations with a Dec 31 year end.
September 30, 2026: UAE Corporate Tax filing deadline for entities with a Dec 31 year end.
October 1, 2026: Deadline to pay UK Corporation Tax for companies with a Dec 31 year end.
December 31, 2026: Deadline to file UK Form CT600 for companies with a Dec 31 year end.

How Gullia Filing Helps

Gullia Filing provides expert support for founders managing entities in the US, UK, Canada, and the UAE. Our team handles your bookkeeping, payroll, and corporate tax filings to ensure you never miss a 2026 deadline. We simplify international compliance so you can focus on scaling your business across borders.

To ensure your 2026 tax strategy is on track, talk to a filing analyst.

2026 Corporate Tax Deadlines: US, UK, Canada, and UAE Guide