But earnings were only 9% higher, at 2 billion USD, since global rice prices have fallen by over 10% to 489 USD a tonne on average.
Exports to the US grew fastest at 65.3%, followed by the Philippines, Vietnam's top market, at 48.6%.
Domestic prices also fell as adverse weather affected rice quality and demand was low compared to previous months.
Exporters have slowed down purchases from farmers and await the peak harvest season.
Vietnam is currently the second biggest rice exporter in the world, just behind India.