An irrevocable trust is a trust that cannot be amended, modified, or terminated by the grantor, settlor, or trustor (person who created the trust) after it is created—at least not without the permission of the beneficiary or beneficiaries.

Irrevocable trusts generally offer tax benefits that revocable trusts do not. This is primarily because the grantor, settlor, or trustor who creates an irrevocable trust permanently transfers (gifts) all right of ownership of the assets to the trust and its beneficiaries.

Laws vary from state to state but a trust is usually irrevocable unless the grantor, settlor, or trustor specifies otherwise in the trust agreement.

In New York, an irrevocable trust is a legal arrangement where the grantor (the person who creates the trust) transfers their ownership rights of the assets to the trust, relinquishing control over these assets. Once established, the trust generally cannot be altered, amended, or terminated by the grantor without the consent of the beneficiaries, except under certain circumstances as permitted by law. Irrevocable trusts are often used for estate planning purposes, as they can provide significant tax advantages. For instance, assets placed in an irrevocable trust are typically not considered part of the grantor's taxable estate, which can reduce estate taxes upon the grantor's death. Additionally, the income generated by the trust may not be subject to income tax on the grantor's personal tax return. New York law, as with other states, has specific provisions and requirements for the creation and administration of irrevocable trusts, and these are outlined in the New York Estates, Powers & Trusts Law (EPTL). It is important for individuals considering an irrevocable trust to consult with an attorney to ensure that the trust is properly established and administered in accordance with New York law and to fully understand the tax implications and legal obligations involved.