Shareholders of Eldorado Resorts and Caesars Entertainment have agreed to combine the two companies in a cash and stock merger.
In June, it was agreed Eldorado would acquire Caesars in a deal worth $17.3bn, initially valued at $18bn by a Reuters report.
The proposed agreement was subject to stakeholder approval from both operators.
Holders of over 99% of Eldorado and Caesars shares have now voted in favour of the merger, along with the reincorporation of Eldorado from Nevada to Delaware following completion of the deal.
The acquistion is expected to be completed in H1 of 2020, subject to all required regulatory approvals.
Activist investor Carl Icahn became Caesars' largest individual stakeholder earlier this year with the aim of pushing through the merger.
A statement from Icahn’s website in June read: "This merger is the quintessential example of how an activist shareholder, working collaboratively with the board, can greatly enhance value for all stockholders."
In a presentation prepared for investors earlier this year, Eldorado used public filings to conclude the joint company’s EBITDAR was the largest in the market, at $3.6bn.