Washington: The US economy was expected to lose $US3 billion ($4 billion) from the partial federal government shutdown over President Donald Trump's demand for border wall funding, congressional researchers said on Monday as 800,000 federal employees returned to work after a 35-day unpaid furlough.

The US Capitol seen during the government shutdown. Credit:AP

The nonpartisan Congressional Budget Office (CBO) said the cost of the shutdown will make the US economy 0.02 percent smaller than expected in 2019. More significant effects will be felt by individual businesses and workers, particularly those who went without pay.

Overall, the US economy lost about $US11 billion during the five-week period, CBO said. However, CBO expects $US8 billion to be recovered as the government reopens and employees receive back pay.

The longest shutdown in US history ended on Friday when Trump and Congress agreed to temporary government funding - without money for his wall - as the effects of the shutdown intensified across the country.