The controversial GOP tax reform bill is unpopular with voters on both sides of the aisle; more than half of Americans say the proposed tax plan would help neither their family’s financial situation nor the U.S. economy, according to research by Gallup.

If that’s true, why is the GOP tax bill moving through Congress? Here’s everything you need to know about the GOP tax bill explained:

What are the GOP tax bill details?

For a bill that sold itself on simplification of the tax code, whether the GOP tax reforms will help or hurt you is difficult to determine – and depends on how you make your money and how much money you make. While the GOP tax bill makes big, sweeping changes to the tax code, it also has inserted small, incremental add-ons during the reconciliation (the process in which the House and Senate negotiate to make their two bills one) that could have huge impacts.

For instance, the GOP tax bill made changes to the current tax brackets. Though there are still seven brackets, the tax reform bill changes the rates paid by filers in each bracket, dropping the rates by as much as 4%. Dropping the 39.6% tax rate on the highest current bracket down to 37% will have a massive impact on the federal budget, which leads to either big spending cuts, a huge deficit, or both. As a result, the Congressional Budget Office has said the GOP tax bill will add at least $1.4 trillion to the deficit over the next 10 years.

Another reason why almost half the voters aren’t in favor of the GOP tax bill: It slashes the corporate tax rate from 35% to 21%. On the whole, this is generally unpopular with people who feel companies have been getting the better end of the stick for years. But small business owners are pleased with the new 20% business income tax deduction for “pass-through” business owners. These taxpayers, who tend to run LLCs, are happy to get relief from higher corporate rates. But it’s not just going to benefit people selling hand-made goods on their Etsy shop. Donald Trump owns 500 pass-through entities, for example, and some members of Congress could personally benefit as well.

But in a nod to the middle class, the GOP tax bill doubles the standard deduction from $12,000 to $24,000 for married couples. That detail alone is designed to simplify filing, as it would encourage people to stop itemizing deductibles in favor of the larger standard deduction.

As the bill has moved through reconciliation, the ground has continued to shift, with some parts that once sparked ire now an afterthought. For example, in a previous version of the GOP tax bill, graduate students were up in arms because tuition wavers were slated to be taxed. But in the final GOP tax bill, Ph.D. students can breathe a sigh of relief because Republicans have backed off on taxing the tuition benefits.

However, throughout reconciliation, one proposal hasn’t changed: the GOP tax bill kills the Affordable Care Act’s individual mandate, something the Republican Party wasn’t able to do through its multiple attempts to repeal the healthcare bill.

If you want to dig into the finer details yourself, you can read the latest version of the GOP tax bill. Or, for a more top line summary, check out these key changes.

When is the GOP tax bill vote date?

The House Rules Committee voted on Monday evening to hold the House vote for the GOP tax bill on Tuesday afternoon, says Reuters. If the bill passes the House, the Senate could then vote on it later Tuesday or Wednesday.

Who is voting on the GOP tax bill?

Both the House and the Senate have to pass the bill in order for it to be sent to President Trump for it to be signed into law.

To clear the House, the GOP tax bill must receive a simple majority, which would be 218 votes. Currently there are 239 Republicans in the house, which means if the GOP tax bill vote goes along party lines, it would clear with ease. Still, there are dissenting Republicans in the House.

Another Republican NO vote on the final tax bill: Rep. Chris Smith of New Jersey will vote against it, his office says.

— Thomas Kaplan (@thomaskaplan) December 18, 2017

To pass the Senate, the GOP tax bill must receive 51 votes, but the math is much more complicated than it seems. The Republican Party currently holds 52 seats. John McCain (R-Ariz.) will miss the GOP tax bill vote, because he had to return to his home state after being hospitalized for a viral infection while battling brain cancer. Jeff Flake (R-Ariz.) meanwhile, appears to be the only undecided Republican, and even if he votes against the bill, Vice President Mike Pence would cast a tie-breaking vote to pass the bill.

Susan Collins (R-Maine), who was one of the nails in the coffin of the Republicans’ Obamacare repeal attempts, is voting for tax reform, despite its inclusion of Obamacare-gutting provisions.

As revised, this bill will provide much-needed tax relief and simplification for lower- and middle-income families, while spurring the creation of good jobs and greater economic growth. (2/2) pic.twitter.com/QB4iM7EdAt

— Sen. Susan Collins (@SenatorCollins) December 1, 2017

In addition, Bob Corker (R-Tenn.) has declared his support for the GOP tax bill, a flip that outraged opponents of the legislation. Originally Corker said he wouldn’t vote for a bill that would impact the deficit so severely. But recently Corker has changed his tune, and some have pointed to recent changes to the bill’s language (called the “Corker Kickback” on Twitter) that could personally enrich the senator. Corker told the International Business Times that he didn’t know about the sweetener, because he hadn’t read the bill in full before changing his mind.

Where can you watch the GOP tax bill vote live?

C-SPAN, PBS, and other news outlets will carry the votes live on television and stream them over the web. But viewers who want to get their news direct from the source should point their web browsers towards the both the House’s and Senate’s streaming live floor proceedings.

What comes after the GOP tax bill vote?

If the GOP tax bill passes, parts of the law will take effect immediately after President Trump signs it into law. For instance, since income rates will be lower, less money will be withheld from paychecks starting early in the new year. But for the most part, changes won’t go into effect until you begin filing your 2018 taxes. But a word of advice: Don’t go dumping your healthcare coverage just because the individual mandate has been repealed. That stipulation doesn’t go into effect until next year, and you will still be penalized if you lack coverage in 2018.

Correction: The original version of this story misstated the number of votes required for a simple majority in the House of Representatives. The number is 218, not 2018.