Irrevocable Beneficiary: An irrevocable beneficiary is someone whose rights to an asset or investment are legally binding and cannot be changed without their consent. This type of beneficiary is often used in wills and trusts, where the funds or assets are meant to go to a specific person, regardless of any changes to the will. Though this security can be seen as beneficial, it also means that beneficiaries have no flexibility in terms of redistributing assets or changing the terms of the trust.