Maureen Groppe

USA TODAY

House Republicans on Monday released their long-awaited proposal to replace the Affordable Care Act, known as Obamacare. While the bill retains several popular provisions of Obamacare — such as requiring insurance companies to cover people with pre-existing conditions — it makes many fundamental changes, including:

Medicaid

Obamacare: More than half the insurance coverage gains under the ACA came from Medicaid, which was expanded to include those earning up to 138% of poverty ($27,725 for a family of three). The federal government pays at least 90% of the costs for those newly eligible in states that expanded the joint federal-state health care program.

GOP bill: Would phase out the expansion. States would receive the extra funding only for people who are enrolled before 2020. Once those beneficiaries leave the Medicaid rolls, the higher funding stops. Would also end the open-ended match states receive for all other Medicaid beneficiaries. Instead, states would be given a set amount of money based on the number of enrollees they had in 2016.

Tax credits

Obamacare: Subsidizes private insurance for those who aren’t offered coverage through an employer and don’t qualify for a government program like Medicare and Medicaid. Those earning up to 400% of poverty ($47,080 for a single person) receive tax credits tied to their income and the cost of plans in their area. Those earning up to 250% of poverty get additional help paying for other out-of-pocket costs like co-payments and deductibles.

GOP bill: Would end the cost-sharing subsidies and no longer adjust the premium credits based on insurance costs. Instead, it would adjust them for age and would also offer them to individuals earning up to $75,000. The nonpartisan Kaiser Family Foundation estimates the change could help people who are younger, higher-income or live in areas where premiums are lower, such as Massachusetts, New Hampshire and Washington. Those who are older, lower-income or live in high-premium areas such as Alaska and Arizona benefit more from the current subsidies.

Insurance mandate

Obamacare: Requires most people buy insurance and that larger employers offer coverage to workers. Imposes fines on those who fail to buy insurance and on employers who don't offer affordable coverage.

GOP bill: Repeals the penalties. Would keep people from jumping into the market only when they need care by allowing insurers to charge them 30% higher premiums for a year.

Age-based premiums

Obamacare: Allows insurers to vary premiums for the same level of coverage only by tobacco use, location and age — within limits. The premiums for a 64-year-old can’t be more than three times the premium for a 21-year-old buying the same plan.

GOP bill: Would let insurers charge older customers five times as much. That’s intended to draw more younger — and healthier — people into the individual insurance market.

USA TODAY coverage of the new GOP health care legislation:

Some Republicans slam their own party's Obamacare repeal plan

Trump team praises House health care bill but will work with critics

Health bill's tax cuts worth $600 billion, mostly for corporations and the rich

GOP Obamacare repeal and replacement plan riles patients, hospitals

Koch groups slam GOP health care replacement plan as 'Obamacare 2.0'

House Republicans unveil Obamacare replacement bill

Poll: Majority of Americans want to keep Obamacare