A general technique for the calibration of metric instruments is applied to the verification of vehicle weighbridges. The technique, called the combinatorial technique, is used to determine both the errors in the weighbridge scale over the verification range and the associated measurement uncertainty. Using suitable equipment, the measurements can be carried out in a time comparable to that of current techniques. The technique has the advantage that the total mass of the standard weights used can be between 5 % and 50 % of the capacity of the weigh bridge. Although reducing the proportion of standard weights increases the uncertainty in calculated scale errors, the technique has sufficient statistical rigor to allow a determination of the degree of confidence in any compliance/non-compliance decision. Examples of the verification of road weigh bridges, up to 40 t, using the technique are given.