In this paper, we show that vessel traffic data based on Automatic Identification System (AIS) can be used to nowcast trade activity. We develop indicators on maritime traffic and trade based on port calls. We use Malta as a benchmark case. Data on port calls track arrivals and departures of vessels based on their positions at ports. We find that an AIS-based indicator tracks well Malta's official volume index of imports. Provided that the challenges associated with port calls data can be overcome through appropriate filtering techniques, these emerging “big data” on vessel positions could allow statistical agencies to supplement existing data sources on trade and introduce new statistics that are more granular (port-by-port) and more timely (practically real-time), offering an innovative way to nowcast trade activity in volume.