to impute - to place a probable value on something, where the actual value is not known; ... where a company occupies its own buildings, an accountant may fix an imputed or notional rent at a figure equal to the rent which the company could get if it leased the buildings to somebody else, i.e. the opportunity cost, imputed cost - estimate of the opportunity cost of making use of a resource that is already owned and so has no formal price. In arriving at the true cost of a process, the imputed cost must be added to the actual outlay