Change of Tax Reference Numbers for Estates/ Trusts/ Unit Trusts
Overview
From July 2026, IRAS will use the 9-character tax reference number (“ASGD ID”) in AXXXXXXXX format as the tax reference number for Estates, Trusts and Unit Trusts. The 10-character tax reference number (“ITR ID”), e.g. 3000123456 / 330012345X, will no longer be used as the tax reference number.
This change supports IRAS’ initiative to introduce new digital services from 2027, to improve taxpayers’ experience and strengthen the security of income tax administration.
From July 2026, IRAS will progressively notify active executors, administrators, legal personal representatives and trustees having obligations to file Form T and Form UT of the new tax reference number (ASGD ID). Some tax notices may still show the old ITR ID as our systems are being upgraded which is expected to be completed by end December 2026. Starting January 2027, all tax notices will use the new ASGD ID.
What you need to do (executors, administrators, legal personal representatives, trustees and tax agents)
- Use the new ASGD ID for all dealings with IRAS (e.g. filings, enquiries and payments).
- Update your internal records and systems (e.g. templates and accounting/tax software) to reflect the new ASGD ID.
- If you have appointed a tax agent, you must provide them with the new ASGD ID so that they can update their records.
- To prepare for new digital services, including Form T or Form UT e-Filing at myTax Portal next year, you will be required to appoint a Corppass Administrator and register an online Corppass Administrator account using the Appointment of Corppass Administrator Form at https://go.gov.sg/estate-trust-corppass by 31 December 2026. The account enables secure access to myTax Portal for Form T/ Form UT e-Filing or delegation to co-trustees or tax agents as needed. Your Corppass Administrator account will be created in early 2027 and your appointed Corppass Administrator will receive an email between January 2027 to February 2027 to set up access to IRAS’ new digital services via Corppass. IRAS will provide further guidance on accessing digital services and the e-Filing of Year of Assessment 2027 Form T or Form UT in the filing notification letter in February 2027.
- If you are already using IRAS' digital services for the Estate, Trust or Unit Trust at IRAS’ myTax Portal, you or your appointed Corppass Administrator must update the new ASGD ID of the Estate, Trust or Unit Trust within the “FOR NON-UEN ENTITY ONLY” digital service at www.corppass.gov.sg by following the steps below to continue using IRAS digital services. There is no need to submit the above-mentioned Corppass Administrator Form to register your Corppass Administrator with IRAS, as your existing Corppass Administrator will be able to use his Corppass account to set up access to IRAS’ new digital services.
Frequently asked questions
IRAS will notify executors, administrators, legal personal representatives and trustees of the ASGD ID of their Estate, Trust or Unit Trust via post. Only Estates, Trusts and Unit Trusts that are required to file income tax returns will be contacted by IRAS.
ASGD IDs are issued only to Estates, Trusts or Unit Trusts that have ongoing tax obligations (e.g. filing or payment matters). If circumstances change and tax obligations arise later, contact IRAS to get an ASGD ID.
No. Use the ASGD ID for all future dealings with IRAS. During the transition period (i.e. from when you are notified of the new ASGD ID to December 2026), IRAS will still be able to identify Estates, Trusts and Unit Trusts that state their ITR ID, and some IRAS notices may still show the ITR ID as our systems are being upgraded. From January 2027, you should use the ASGD ID for all dealings with IRAS, including when using IRAS digital services at myTax Portal. The ITR ID will no longer be used.
Update any payment records or standing instructions to use the ASGD ID once the ID has been issued to you. During the transition period (i.e. from when you are notified of the new ASGD ID to December 2026), IRAS can still match payments that quote the ITR ID to the correct Estate/ Trust/ Unit Trust. From January 2027, you should use the ASGD ID for all dealings with IRAS.
Email trust@iras.gov.sg to enquire about the assigned ASGD ID. Please provide the name of the Estate, Trust or Unit Trust, the old 10-character ITR ID and supporting documents showing that you are an authorised person to act for the Estate, Trust or Unit Trust.
Tax agents should first obtain the ASGD ID from their clients. If they are unable to do so (e.g. if IRAS’ notification letter on the tax reference number change is misplaced), they may submit a request via https://go.gov.sg/trustidrequest between August to December 2026. IRAS will provide the requested information after verification. Please submit one request per tax agent firm.