Republicans say the tax bill, which has been a major focus of President Donald Trump’s time in office, will provide $1.5trn (£11.2trn, €12.6trn) in tax cuts which will revitalise the US economy.
The Senate passed the bill by 51 to 48 votes on 19 December with every Republican voting for it, except John McCain who was not present due to ill health.
The house also passed the bill on same day as the senate by 227 to 203. However, after the vote, it was discovered that two parts of the bill had to be removed as they clashed with strict senate budget rules.
Because of the clash the house is required to hold another vote to pass the bill on the morning of 20 December.
Estate tax exemption rises
Once the bill passes into law it will raise the exemption for estate and gifts taxes from $5m to $10m per person and will index the new exemption level to inflation.
Despite the raised exemption for estate tax, many conservative Republicans say the plan falls short of pro-growth expectations.
Earlier this month 54 House Republicans pressured the Ways and Means Committee, who were reviewing the bill, to repeal the estate tax altogether from the bill. The committee did not fold to the pressure however and estate tax has remained in the plan.
A group of Republicans, known as the Club for Growth, say they will try again next year to have estate tax eliminated completely from the plan.
Additionally, the group wants alternative minimum tax and the Affordable Care Act taxes to be fully repealed.
“There’s no reason we have to wait another 30 years to enact additional reform,” president of the Club for Growth David McIntosh said to The New York Times.
President Trump is expected to sign the bill into law soon after the final house vote.