President Trump and congressional Republicans unveiled their plan for a massive tax overhaul.

The plan, meant to be a framework for Congress to negotiate into legislation, still has missing parts. And as the House prepares to vote on the Senate’s budget plan Thursday, some lawmakers, including Republicans, still have qualms with parts of the tax framework.

One issue is whether to curb tax-free deposits in 401(k) retirements accounts, something that Trump has said he opposed. Ways and Means Committee Chairman Kevin Brady, R-Texas, wants to curtail them.

White House press secretary Sarah Sanders declined to "negotiate" and speculate on if Trump could work with lawmakers and change the 401(k) rules but told Fox News Thursday morning that he is "committed" to protecting the middle class' retirement accounts.

"The president will get much of what he wants I think in tax reform, but we are a co-equal branch," said Sen. Pat Toomey, R-Pa. "And we're going to write it."

But read on for a look at who wins and loses under the proposal as it stands now.

Winners

Corporations with high tax rates: The framework lowers the corporate tax rate to 20 percent from 35 percent. Trump initially wanted to lower it to 15 percent but said his “red line” for the rate is 20.

It also lowers the tax rate for small businesses to 25 percent. The majority of small business owners would use the extra cash to expand businesses and hire additional employees, Alfredo Ortiz, president of the nonprofit Job Creators Network, told Fox News.

Heirs to large estates: The plan eliminates the so-called death tax, or estate tax. The federal estate tax, which typically affects wealthier Americans, is a tax on property transferred after the owner’s death.

People who do their own taxes: With the framework, Republicans hoped to simplify the tax code and the way Americans file their taxes. The plan collapses the number of brackets from seven to as little as three.

High-income households: The framework includes multiple tax cuts for high-income taxpayers, including the elimination of the Alternative Minimum Tax. The AMT is a supplemental income tax meant to offset benefits a person with a high income could receive.

Low-income households: The plan doubles the standard deduction, which reduces the amount of taxed income, to $12,000 for individuals and $24,000 for married couples, making low-income taxpayers a winner, Steve Odland, CEO of the Committee for Economic Development, told Fox News.

It also increases the child tax credit which could be beneficial to families.

Losers

Taxpayers in high-tax states: The plan eliminates state and local tax deductions, meaning taxpayers in states with high taxes will lose out on the write-off. This impacts those in mostly blue states, such as California and New York.

Congressional Republicans in New York and New Jersey have warned that they’ll reject the Senate’s budget plan Thursday as they are upset over this provision.

Accountants: Because the plan would streamline the tax process, less people would potentially need to hire tax accountants, lawyers and firms, Odland predicted.

Trump has said he wants to put H&R Block "out of business."

National debt: The plan would result in approximately $2.2 trillion of net tax cuts -- a blow to the national debt, the Committee for a Responsible Federal Budget said.

“Given today’s record-high levels of national debt, the country cannot afford a deficit-financed tax cut,” the nonprofit said.

Social programs: With the greatly reduced amount of tax collections the plan calls for, it’s possible that domestic spending on programs such as welfare programs and education could take a hit, Henry Aaron, a senior fellow at the Brookings Institution, told Fox News.

People who want a concrete plan: Aaron also said the plan was lacking in details, making it difficult for policy experts to come up with concrete estimates of the framework’s impact.

“People can make assumptions about what the details will be and make estimates based on their assumptions, but you won’t really know until the details are in,” he said.

The Associated Press contributed to this report.