He explained that an overhaul was urgently needed in a country where about 30 million people cannot get health insurance.
Al Jazeera's Rob Reynolds, reporting from Capitol Hill where Obama made his speech, said the healthcare issue was one of Obama's sternest tests as president so far, and could be pivotal to his presidency.
Although the Democrats have control of the upper and lower houses of congress, failure to win broad support on changes to the healthcare system could weaken Obama politically and negatively affect other items on his policy agenda, our correspondent said.
The formulation of a healthcare bill suitable to both Democrats and Republicans has so far proved elusive, despite the efforts of a six-member bipartisan panel tasked with drafting a new policy.
Warning that the US deficit would grow, more families and businesses would go bankrupt, and more people would die if congress did nothing, Obama said: "Our collective failure to meet this challenge - year after year, decade after decade - has led us to a breaking point.
"Everyone understands the extraordinary hardships that are placed on the uninsured, who live every day just one accident or illness away from bankruptcy."
Obama's speech was designed to retake control of the debate after his plans for change came under fire from Republicans and conservative groups.
They allege that Obama's package amounts to a socialist takeover of the US healthcare system, and that spending $1 trillion on the overhaul is irresponsible at a time when the US is struggling under its highest-ever budget deficit.
Obama hit out at his critics on Wednesday, dismissing "bogus claims spread by those whose only agenda is to kill reform at any cost" and saying that many had used the opportunity to "score short-term political points".
"The time for bickering is over, the time for games has passed," he said.
The president said his plan would meet three basic goals: provide more security and stability to those who have health insurance, provide insurance to those who do not have it, and slow the growth of healthcare costs.
He outlined details of the plan that would offer consumer protections for those already with insurance, an exchange that allows individuals and small businesses to purchase affordable coverage, and a requirement that people who can afford it to be insured so that taxpayers are not saddled with the costs of the uninsured.
Jim Clyburn, the Democratic majority whip in the House of Representatives, told Al Jazeera that Obama's speech gave clarity to the five different committees working on healthcare reform proposals.
"What we've come away from tonight is a clear idea of what we ought to be doing for people who have insurance and what we need to do for people who do not have insurance and exactly what we need to do to contain costs," he said.
He also said the president had done "exactly what he needed to do" to calm the fears of legislators on the left of the political spectrum who believe strongly in the need for a so-called public option - a government-run insurance programme.
Promising that the plan would not add "one dime to our deficits either now or in the future", Obama said there would be a provision that requires the government to come forward with more spending cuts if the savings promised do not materialise.
He said most of the new plan "will be paid for with money already being spent but spent badly in the existing healthcare system".
And he pointed out that at an estimated cost of $900bn over 10 years, it was "less than we have spent on the Iraq and Afghanistan wars and less than the tax cuts for the wealthiest few Americans that congress passed at the beginning of the previous administration".
Christopher Hayes, the Washington editor of the progressive magazine, The Nation, agreed that Obama had been "very clear" in laying out the basic structure of the healthcare policy.
But he told Al Jazeera that "there is a tremendous amount of frustration from progressives" over what they see as Obama not being progressive enough and trying to appease conservatives.
"At a certain point it becomes a question of gain theory and what hurts him more politically - appeasing the right and forgetting his base, or listening to his base and forgetting the right," he said.
"The way the balance of power works in this country is that the left is consistently marginalised and the balance of power tends to be with Wall Street, the health insurance companies and the right-wing, and that's a power imbalance that is bigger than just Barack Obama, that's really the root problem."