A trust in which a beneficiary has an entitlement to a fixed income.
"A fixed trust is a trust in which a beneficiary has a current fixed entitlement to an ascertainable part of the net income, if any, of the trust fund after deduction of sums paid by the trustees in the exercise of their administrative powers of management. The beneficiary has an interest in possession under the trust."
A fixed trust is often contrasted with a discretionary trust, as the latter gives the beneficiary's no certain hope to any residue and no title of ownership to the trust itself.
Hayton, David, Underhill and Hayton Law Relating to Trusts and Trustees, 17th Ed. (London: LexisNexis-Butterworths, 2006), page 85.