After a decline of $2.4 billion in February to a downwardly revised $43.6 billion, the bureau said the trade gap shrank by $4.8 billion to $38.8 billion in March.
The gap closed as with exports down by $1.7 billion compared to February and imports off by $6.5 billion compared to the previous month.
Economists had expected the trade gap to shrink, but only to $42 billion.
As per usual, the trade balance included a deficit in goods and a surplus in services. For March, the trade gap in goods trading dropped by $4.6 billion to $56.1 billion, while the surplus in services rose by $200 million to $17.3 billion.
Among major trading partners, the trade gap with China dropped from $23.4 billion in February to $17.9 billion in March. With the Organization of Petroleum Exporting Countries, the gap increased from $3.6 billion to $4.5 billion.
The trade deficit with the European Union rose from $8.8 billion to $9.9 billion, and with Japan it rose from $5.9 billion to $6.6 billion, the bureau said.