Can a creditor enforce a judgment against assets held in a trust in Ontario?

Generally, no — not directly, and this is one of the reasons trusts are sometimes used for asset protection planning. Where a debtor is only a beneficiary of a trust, rather than the person who controls it, the trust's assets legally belong to the trust, not to the debtor personally, so an ordinary judgment against the debtor generally can't simply be enforced against those assets the way it could against something the debtor owns outright. A creditor may still be able to reach a beneficiary's actual entitlement to receive money or property from the trust, once and if that entitlement becomes fixed and payable, but reaching the underlying trust assets themselves is much harder.

This protection isn't absolute. If the trust was set up, or a transfer into it was made, specifically to defeat a known or anticipated creditor, a court may be willing to unwind that transfer or otherwise look past the trust structure. Similarly, if the debtor effectively still controls the trust assets as if they were their own, despite the formal trust structure, a court may look at the substance of the arrangement rather than its form. Because trust structures and creditor remedies here are genuinely complex, this is an area where specific legal advice matters considerably.