Among them are a "better definition of who qualifies for family and medical leave", greater OSHA protection for workers, a proposal for pensions that Pelosi said President Trump approved and Senate Majority Leader Mitch McConnell, R-Ky., said could be in the next bill, a 15 percent increase in food stamps, and additional funds for state and local governments.
Senate Democratic leader Chuck Schumer called it an "outstanding agreement".
Legislative text of the final deal was released Wednesday evening ahead of a final vote.
President Trump and top members of his administration gave their strong support to the bill Wednesday. Pelosi said she spoke with Treasury Secretary Steven Mnuchin about directing as much assistance as possible to local efforts to deal with the outbreak and speeding aid to small businesses by going through banks as well as the Small Business Administration.
The plan includes about $500 billion that can be used to back loans and assistance to companies, including $50 billion for loans to USA airlines, as well as state and local governments. It also has more than $350 billion to aid small businesses.
In addition, the bill would provide a major amount of funding for hard-hit hospitals - $130 billion - as well as $150 billion for state and local governments that are cash-strapped due to their response to coronavirus.
Individuals earning less than $75,000 in adjusted gross income would directly receive $1,200 each.
Unemployment insurance would be extended to four months, the benefits would be bolstered by $600 weekly and eligibility would be expanded to cover more workers.
The largest chunk of money provided by the bill goes to large industries and corporations, with $500 billion provided for a host of industries deemed vital to the economy, including at least $32 billion for the airline industry.
There are also provisions to ban stock buybacks for the term of government assistance, plus an additional year for any company receiving a government loan from the bill. The loans will be forgiven if the companies retain their employees and meet other conditions.
The Senate is expected to vote on March 25 and President Trump will sign the bill shortly after.
With the prospect that Congress was closing in on a deal Tuesday, the Dow Jones Industrial Average rose more than 11 per cent in its biggest advance since 1933, and the S&P 500 rebounded with the biggest one-day gain since October 2008 after starting the week with a rout. In Asia markets, USA futures pared early losses after news of the deal. Among those, it creates a Treasury Department special inspector general for pandemic recovery and a Pandemic Response Accountability Committee to oversee loans to businesses.
Schumer also said that hundreds of billions would be spent on Democratic priorities, including the expansion of unemployment benefits, money for hospitals as well as more funding for cities and transportation. Republicans were tepid about the package, but Trump endorsed it and it ultimately passed Congress with the support of 90% of lawmakers in both chambers.
The bill, considered to be largest stimulus package in the U.S. history, aims to support unemployed workers and industries impacted by the deadly virus, as well as to provide billions of dollars to buy urgently needed medical equipment.
That would also require the unanimous consent of all House Republicans.
Aimed at getting the money to Americans and businesses amid the pandemic, the bill's next stop is the House of Representatives, which is scheduled to vote on it Friday.
Direct cash payments: Most Americans will get checks of up to $1,200 plus $500 per child, at a cost of about $290 billion.
Legislation heads to the House next.