The rules, effective for financial years starting on or after 1 January 2025, require in-scope multinational groups to prepare for registration from May 2026 and ensure compliance with new reporting and filing obligations aimed at securing a 15% minimum effective tax rate.

The Inland Revenue Authority of Singapore (IRAS) has revised its guidance on the registration requirements for the Multinational Enterprise Top-up Tax and the Domestic Top-up Tax.

Following the 2024 Budget, Singapore has introduced new global minimum tax rules under the Multinational Enterprise (Minimum Tax) Act 2024. These apply from financial years starting on or after 1 January 2025.

Two key taxes are introduced:

  • Multinational Enterprise Top-up Tax (MTT): Applies to low-taxed profits of overseas group entities (aligned with the OECD Income Inclusion Rule).
  • Domestic Top-up Tax (DTT): Applies to low-taxed profits of Singapore-based group entities.

Together, these ensure large multinational groups pay at least a 15% effective tax rate under the OECD Pillar Two framework.

Who must register

An MNE group must register if:

  • It has global revenue of at least EUR 750 million in at least two of the last four financial years, and
  • It has at least one:
    • Entity, joint venture, or reverse hybrid entity in Singapore.

Registration timeline and process

  • Registration begins: May 2026
  • Deadline: Within six months after the first relevant financial year ends

Example:

  • FY: 1 Jan 2025 – 31 Dec 2025
  • Deadline: 30 June 2026

If a group has a short financial year in 2025, it may request an extension by emailing IRAS.

Who submits registration

  • The Ultimate Parent Entity (UPE) must submit the registration form.
  • Submission is done via an online IRAS form.
  • A representative (from Singapore entity or tax agent) may submit if authorised.
  • A Letter of Authorisation is required if a representative is used.

Information needed for registration

MNE groups must prepare:

  1. Entity details
  • Tax Identification Numbers (TINs) of all Singapore-linked entities, including:
    • Constituent entities (including permanent establishments)
    • Joint ventures
    • Minority-owned entities
    • Investment/insurance entities
    • Reverse hybrid entities
    • Excluded entities
  1. Additional reporting details
  • Tax residency details and changes (for relevant entities)
  • Details of entities that changed tax residency after 30 Nov 2021
  1. Filing entity appointments
  • Designation of:
    • GloBE Information Return (GIR) filing entity
    • Domestic Top-up Tax (DTT) filing entity
  • Contact details of responsible personnel
  1. Financial year information
  • Start and end date of first applicable financial year

Large groups (30+ entities) must use IRAS templates instead of manual entry.

After registration

  • Processing time: about one month (longer if incomplete)
  • IRAS issues confirmation emails and notification letters
  • A Group Identification Number (Group ID) is assigned

Filing arrangements

DTT and GIR filing

  • Filed via myTax Portal using the Group ID
  • Default Corppass Administrator setup:
    • The administrator for the filing entity becomes the Group ID administrator
  • Filing starts from January 2027

MTT filing

  • Filed using the Responsible Member’s UEN
  • Each entity already has its own Corppass setup
  • Used for authorising access to tax services

Penalties

  • A 10% surcharge may apply if an in-scope group fails to notify IRAS of its registration requirement.

Key takeaway

Large multinational groups operating in Singapore must prepare early for:

  • Registration (from May 2026)
  • Detailed entity reporting requirements
  • New digital filing systems from 2027

All aimed at enforcing a 15% global minimum tax under Pillar Two rules.