It defines a recession as a decline in economic activity that lasts more than a few months.
The committee noted, though, that in this case, the depth of the downturn since February had led it to determine that a recession had begun.
The unprecedented magnitude of the decline in employment and production, and its broad reach across the entire economy, warrants the designation of this episode as a recession, even if it turns out to be briefer than earlier contractions, the NBER panel said.
The unemployment rate is officially 13.3 per cent, down from 14.7 per cent in April. Both figures are higher than in any other downturn since World War II.
A broader measure of underemployment that includes some of the unemployed who have given up looking and those who have been reduced to part-time status is 21.2 per cent.