The UAE corporate tax deadline for companies with a financial year ending 31 December 2025 falls on 30 September 2026. By that date, both free zone and mainland businesses must file their Corporate Tax return and pay any tax due to the Federal Tax Authority (FTA).
However, filing is only part of the picture. As the regime enters its second full cycle, free zone and mainland companies are taxed in increasingly different ways. Many foreign-owned companies still assume that a free zone licence automatically means 0% tax. In reality, it does not.
The UAE corporate tax deadline at a glance
Taxable persons generally have nine months from the end of their tax period to file their return and settle their liability. For companies with a calendar-year tax period, the cut-off is therefore 30 September 2026. Returns are submitted through the FTA’s EmaraTax portal.
This obligation applies to every taxable person. It includes free zone entities that expect to pay no tax at all.
How mainland companies are taxed
Mainland companies follow the standard banded system. Taxable income up to AED 375,000 (around USD 102,110) is taxed at 0%, and income above that threshold is taxed at 9%.
In addition, eligible resident businesses with revenue of up to AED 3 million can elect for Small Business Relief. The Ministry of Finance recently extended this relief by three years. For more details, read our article on the UAE Small Business Relief extension to 2029: https://kelmer.com/uae-small-business-relief-extended-to-2029-opportunities-for-italian-smes-in-the-emirates/
How free zone companies are taxed
Free zone rules work differently. A Qualifying Free Zone Person (QFZP) pays 0% only on Qualifying Income, while any Non-Qualifying Income is taxed at 9%.
The key point is that, according to FTA guidance, QFZPs do not receive the AED 375,000 zero-rate band on income that fails the Qualifying Income test. As a result, the 9% rate applies to the entire non-qualifying amount. Moreover, QFZPs cannot elect for Small Business Relief.
What it takes to keep QFZP status
Ministerial Decision No. 229 of 2025 updated the qualifying activity rules from September 2025. It also made audited financial statements a condition for keeping QFZP status.
Non-qualifying revenue must also stay within the de minimis limit, which is the lower of 5% of total revenue or AED 5 million. Businesses that breach this limit lose QFZP status from the start of that tax period and for the four following tax periods. In other words, a single breach can cost a company the 0% rate for five years.
What foreign companies should check before filing
Before submitting the return, companies should review:
- how each revenue stream is classified, as qualifying or non-qualifying
- whether non-qualifying revenue stays within the de minimis limit
- whether audited financial statements are in place
- whether the current free zone or mainland structure is still the most efficient option for the years ahead
How Kelmer Group can help
Our Dubai team supports foreign companies at every stage of their presence in the UAE. This covers choosing between a free zone and a mainland structure, company setup, accounting, Corporate Tax registration and filing, and ongoing compliance. As the rules become more detailed, careful planning is the best way to protect your tax position and avoid costly mistakes.
Contact our Dubai team at kelmer.com/dubai/
Source: Arabian Business — UAE corporate tax costs for free zones and mainland entities: https://www.arabianbusiness.com/business/uae-corporate-tax-free-zones