After years of trying to repeal and replace the Affordable Care Act, aka Obamacare, Republicans finally got their chance with the election of President Trump. The House GOP made haste coming up with a bill, releasing the American Health Care Act on March 6. It’s a partial repeal of Obamacare — it includes substantial changes to the law, but when it comes to health insurance coverage and how people get it, the GOP bill largely works within the framework set up by the Affordable Care Act. As the House GOP prepares for a vote on the bill, which could come as early as this week, here’s a look at how the AHCA would change the health insurance landscape and who would be most affected by the changes.

If you’ve been following the health care debate, you might have seen that under the GOP plan, fewer people would be insured and the government would spend less on health care over the next 10 years:

But as was the case with the ACA, the biggest changes to health insurance under the GOP plan would be experienced by two groups of people: those with very low incomes and those seeking to buy insurance who cannot get it through an employer — they buy what is often called non-group coverage.

Let’s look at Medicaid, which would undergo significant changes under the GOP proposal. Obamacare allowed states to expand the health insurance program for the poor to cover a lot more people. Traditionally, the program provided coverage for pregnant women and children, people with disabilities, and older adults in need of long-term care. Under Obamacare, states can cover anyone earning less than 138 percent of the federal poverty line (about $16,000 for an individual). The GOP plan freezes the expansion after 2019, which would automatically cancel the expanded program in some states and cause most people who received Medicaid under expansion to lose coverage in the rest of the states within a few years.

The GOP plan also would cap the amount of money that could be spent on Medicaid enrollees, which experts say would reduce both the number of people covered by the program and the coverage those in the program receive.

Even though they are a small percentage of the population, people whose incomes are too high for Medicaid but don’t get insurance from an employer have historically had a hard time buying health insurance, often because it was too expensive or they were denied coverage because of a pre-existing health condition. Obamacare created insurance marketplaces for these people to buy coverage:

Obamacare changed who could buy what kinds of plans, by prohibiting insurers from denying people coverage based on their health status and creating requirements about the kind of coverage insurers could offer. It also provides money to help people buy insurance, subsidies that are calculated based on income and where people live. Under the GOP bill, insurers could sell different kinds of plans (namely ones that are cheaper but offer less coverage), and subsidies would be based only on age. This change would mean that some people, likely those who are younger and healthier, might get more help buying insurance and would be able to buy cheaper plans. But people who are older and live in more rural areas would end up with less help to buy insurance and more expensive plans.

Most people who are younger than 65, however, get coverage from their employer. Their insurance plans are likely to see steady increases in the price for premiums and deductibles regardless of whether the GOP bill passes.

The GOP bill also would roll back several taxes created by the ACA. They are taxes that largely affected business and the top 1 percent of earners.

TAX PROVISIONS THAT WOULD BE REPEALED RANK OF EARNERS NET INVESTMENT INCOME TAX MEDICARE TAX ON HIGH EARNERS Top 1 percent +1.6% – +0.5% – Top 20 percent +0.5 – +0.2 – Second quintile 0.0 0.0 Third quintile 0.0 0.0 Fourth quintile 0.0 0.0 Lowest 20 percent 0.0 0.0 Change in after-tax income if ACA tax provisions are repealed Source: Tax Policy center

There are other measures included in the bill; it would severely limit when federal funding could be used for health services at Planned Parenthood clinics for a year and cut funding for public health programs, among other changes. And the bill isn’t set in stone. House Speaker Paul Ryan suggested that Republicans would add amendments this week, including a work requirement for Medicaid recipients and further subsidies for older people buying insurance on the marketplaces set up by the Affordable Care Act. Ryan also said Republican leaders still plan to bring the bill for a vote in the House on Thursday.