The assessment of nominal effort is a key issue for the estimation of total catches. However, in many datacollection systems, total effort is inferred from sampling schemes at landing points or calculated from fishing forms or logbooks, which do not provide accurate information on a vessel's fishing activity. This problem is especially significant in small-scale fleets where fishers' behaviour and related fishing activity are heterogeneous. As fuel consumption by fishers is often subject to tax relief, it is registered by administration and can be used to improve and cross-check nominal effort measures (hours at sea, days at sea). This paper presents a methodology developed, using this type of dataset, for French West Indies fisheries. The protocol implemented was in three steps and used different data sources. First, a statistical analysis of engine power, engine type, and fuel consumption per métier was carried out based on field studies and fleet register information. Second, an algorithm was developed in order to estimate the number of trips and engine hours per vessel from vessel fuel consumption and vessel tank fill-ups, registered by the administration. Third, these estimates were used to provide a first assessment of the fleet landings per species and discuss the use of this information for calculation of revenue and running cost per trip, including fuel costs. Keywords: fuel consumption, nominal effort, engine power, catches estimates, running costs.