A spendthrift trust is a trust in which the person who makes the trust and places property or assets in it (the grantor, settlor, or trustor) includes a provision that prohibits the beneficiary’s interest in the trust from being assigned to another person or entity—whether as a gift or as collateral for a loan or debt—and prevents a creditor from reaching or attaching the beneficiary’s interest in the trust.

A spendthrift is a person who spends money wastefully or foolishly and a spendthrift provision in a trust (a spendthrift trust) is designed to preserve the trust’s assets and protect the beneficiary from the beneficiary’s spendthrift ways.

In Idaho, a spendthrift trust is a legal arrangement that allows a grantor to place assets in a trust with specific provisions that prevent the beneficiary from squandering the trust's assets. Idaho law recognizes the validity of spendthrift provisions in trusts, which restrict the beneficiary's ability to transfer their interest in the trust and also protect the trust assets from the beneficiary's creditors. Under Idaho Code § 15-7-502, a spendthrift provision is enforceable to prevent voluntary or involuntary transfer of a beneficiary's interest. However, there are exceptions where creditors can reach the trust assets, such as claims for child support, alimony, or services provided to protect the beneficiary's interest in the trust. It's important to note that while spendthrift trusts offer protection for the assets from the beneficiary's imprudent spending and their creditors, they must be properly structured to comply with Idaho laws and to ensure their effectiveness.