Singapore’s 15% minimum tax: registration, central filing and safe harbours

Country reference

• Country: Singapore (Wave 1 expansion country)
• Authorities: Inland Revenue Authority of Singapore (IRAS); Ministry of Finance (MOF)
• Topic: Multinational Enterprise Top-up Tax (MTT) and Domestic Top-up Tax (DTT) under Pillar Two
• Key date: Registration opened May 2026; 30 June 2026 deadline for groups with a 31 December 2025 year end
• Law: Multinational Enterprise (Minimum Tax) Act 2024

The rules in brief

Singapore applies two top-up taxes to financial years beginning on or after 1 January 2025, so that large multinational groups pay an effective rate of at least 15%. The MTT applies to low-taxed profits of group entities outside Singapore. The DTT applies to low-taxed profits of group entities in Singapore.

Who is in scope

• Annual revenue of EUR 750 million or more in the ultimate parent’s consolidated financial statements, for at least two of the four preceding financial years; and
• At least one constituent entity or joint venture located in Singapore, or a reverse hybrid entity incorporated or registered there.

Registration

• One-time online registration for MTT, DTT and filing of the GloBE Information Return.
• Due within six months after the end of the group’s first in-scope financial year. For a year ended 31 December 2025, that was 30 June 2026.
• The ultimate parent files, or authorises a Singapore entity or local tax agent by letter.
• The group appoints a Singapore entity as designated local filing entity for both the GloBE return and the DTT return, and receives a Group ID for myTax Portal.
• IRAS may impose a 10% surcharge on DTT and MTT if an in-scope group fails to notify it.

What changed in 2026

• 14 April 2026: Singapore signed the Multilateral Competent Authority Agreement on the Exchange of GloBE Information. A group can file its GloBE return in one jurisdiction and have it exchanged, which cuts the number of filings for Singapore-headquartered groups.
• Side-by-Side package: IRAS says the Act and Regulations will be amended by end-2026, subject to Parliament, to extend the Transitional Country-by-Country Reporting Safe Harbour and adopt new safe harbours for financial years starting on or after 1 January 2026.
• Revenue: the Budget 2026 Statement expects higher corporate tax collections from FY2027.

What to do now

• Groups with non-December year ends: count six months from the first in-scope year end and register.
• If the date has passed, contact IRAS; do not submit a second form to correct errors, email IRAS instead.
• Decide where the group will file the GloBE return and confirm that jurisdiction exchanges with Singapore.

Our take

For groups headquartered in the Gulf with a Singapore subsidiary, the test is group revenue, not the size of the Singapore entity. A small regional office can bring a registration duty. Check scope at group level and assign the filing entity early.