How Singapore’s ASGD IDs Are Transforming Tax Reference Numbers for Trusts and Estates

What’s Changing

From July 2026, IRAS will begin transitioning estates, trustees, and unit trusts to a new tax reference format: ASGD ID (format AXXXXXXXX). The old format — the 10-character ITR ID (e.g., 3000123456 or 330012345X) — will be phased out. This change is rolling out gradually and is part of IRAS’ push to support new digital services launching in 2027. (iras.gov.sg)

Who’s Affected

• Executors, administrators, legal personal representatives, and trustees who are required to file Form T or Form UT. (iras.gov.sg)
• Any existing tax agents working on behalf of these entities; your records will need updating too. (iras.gov.sg)

What You Need to Do Now

• Once notified by IRAS of the ASGD ID, start using it for all filings, enquiries, and payments — even during the transition. (iras.gov.sg)
• Update internal systems, templates, forms, accounting records to use ASGD ID instead of ITR ID. (iras.gov.sg)
• If you appointed a tax agent, share the ASGD ID with them so everything is kept consistent. (iras.gov.sg)
• Register or appoint a Corppass Administrator by 31 December 2026, ideally ahead of using the upcoming e‐Filing services in 2027. (iras.gov.sg)

The Big Picture: Why It Matters

• It supports IRAS’ digital services rollout which will offer e-Filing for estates, trusts, and unit trusts through myTax Portal in 2027. (iras.gov.sg)
• Strengthens security in tax administration and ensures consistency in reference numbers. (iras.gov.sg)
• Helps prevent mismatches: even during the transition (July–December 2026), IRAS will match old ITR IDs for payments submitted to them while systems are being updated. (iras.gov.sg)

Example Scenario

You’re the administrator of a trust that files Form UT annually. Your ITR ID was 3000123456. In August 2026, IRAS sends you a notification that your trust’s new ASGD ID is A12345678.

Starting immediately, you:

• Use A12345678 on all correspondence to IRAS.
• Update your accounting software and any internal templates to show the new ID.
• Provide this ASGD ID to your solicitor or tax agent.
• Register a Corppass Administrator by 31 Dec 2026 to use upcoming digital services. At payments or filings during this year, IRAS will still accept ITR ID where necessary; after January 2027, only ASGD IDs are valid. (iras.gov.sg)

If you manage an estate, trust or unit trust, double check whether you’ve been notified of an ASGD ID yet; if not, reach out to IRAS to avoid delays when digital services go live in 2027.