Compliance
Digital Identity & Tax Reference Overhaul: Estate, Trust & Unit Trust Taxation in Singapore
Singapore introduces a new ‘ASGD ID’ tax reference number for Estates, Trusts and Unit Trusts to modernise its tax system—mandatory from early 2027.
By NomadicTax Research Team • 5-8 min read • August 13, 2026
## What’s Changing?
Effective **July 2026**, Singapore’s Inland Revenue Authority (IRAS) began using a **new 9-character tax reference number (ASGD ID, format AXXXXXXXX)** for all Estates, Trusts, and Unit Trusts, replacing the old 10-character “ITR ID” (e.g. 3000123456 / 330012345X).([iras.gov.sg](https://www.iras.gov.sg/taxes/other-taxes/trusts/change-of-tax-reference-numbers-for-estates--trusts--unit-trusts/change-of-tax-reference-numbers-for-estates--trusts--unit-trusts?utm_source=openai))
The shift is part of IRAS’ digital transformation drive ahead of new services in 2027. During this transition, both references may still appear on notices, but starting **January 2027**, all formal communications will use **only** the ASGD ID.([iras.gov.sg](https://www.iras.gov.sg/taxes/other-taxes/trusts/change-of-tax-reference-numbers-for-estates--trusts--unit-trusts/change-of-tax-reference-numbers-for-estates--trusts--unit-trusts?utm_source=openai))
## Why It Matters for You
- **Action required:** Executors, trustees, legal representatives, and agents should ensure they use the new ASGD ID for all communications, filings, payments, and dealings with IRAS.
- **System updates:** Internal records, tax software, estate or trust templates must be revised to reflect the ASGD format.
- **Agent communication:** If you rely on a tax agent, provide them with the new ASGD ID to ensure compliance.
## Example Scenario
Imagine you're a trustee managing a trust with ITR ID **330012345X**. You receive your ASGD ID notification in **August 2026**, listed as **A12345678**. From that point:
- Use **A12345678** on all filings or payments
- Between Aug–Dec 2026, IRAS will accept either ID, but from Jan 2027, **only** ASGD ID is valid
- Ensure your accounting system is updated to generate invoices, notices, and internal tracking using ASGD ID
## Tips to Smooth the Transition
- Begin updating stationery, electronic signatures, internal tax accounting, and tax agent records before the end of 2026.
- Watch for your notification letter from IRAS assigning the ASGD ID—only certain estates/trusts with ongoing tax obligations will receive these.([iras.gov.sg](https://www.iras.gov.sg/taxes/other-taxes/trusts/change-of-tax-reference-numbers-for-estates--trusts--unit-trusts/change-of-tax-reference-numbers-for-estates--trusts--unit-trusts?utm_source=openai))
- During audits or tax reviews, referencing the old ITR ID past January 2027 could lead to confusion or delays.
## Insights & Strategic Takeaways
- This reflects a broader ASEAN/SG trend toward **digital identity and secure tax administration**. Strong emphasis on electronic interaction, identity verification, and reducing offline dependency.
- Entities outside Singapore must note that **future consensus and standards may follow** — if you interact across jurisdictions, adopting digital-first, secure ID practices will offer advantages.
**Action plan checklist:**
- Update your tax records with ASGD ID once notified
- Upgrade your tax software templates by Dec 2026
- Inform your tax agent
- Use the ASGD ID in all correspondence from Jan 2027 onward