A new official report shows a record number of Americans are living in poverty.

There were 43.6 million Americans living in poverty last year, the highest number since the US Census began keeping records 51 years ago.

It means the nation's poverty rate was 14.3 per cent in 2009, Barack Obama's first year in office.

The US sets the poverty level at almost $US22,000 a year for a family of four.

The number of people without health insurance also rose last year, sweeping past the 50 million mark for the first time.

Just under 51 million Americans had no health insurance in 2009, up from 46.3 million in 2008, according to the census report.

"This is the highest number of uninsured since 1987, the first year comparable health insurance data were collected," said David Johnson, head of the US Census Bureau's housing and household economic division.

Mr Johnson linked the spikes in both the number of poor and uninsured in the US to the dull economy and rising unemployment.

Median incomes held steady at just under $US50,000 a year, warding off an even sharper rise in the number of people living in poverty, which experts had predicted would reach 45 million.

Mr Obama seized on the glimmer of good news among the bad, saying the steps taken by his administration had helped millions of Americans to keep their heads above water in an ailing economy.

"Last year we saw the depths of the recession, including historic losses in employment not witnessed since the Great Depression," Mr Obama said.

"Today the Census Bureau released data that illustrates just how tough 2009 was. But the data released today also reminds us that a historic recession does not have to translate into historic increases in family economic insecurity.

"Because of the Recovery Act and many other programs providing tax relief and income support to a majority of working families - and especially those most in need - millions of Americans were kept out of poverty last year."

- ABC/AFP