InBev is to acquire Anheuser-Busch for $52bn.
The new company will be called Anheuser-Busch InBev and will be one of the five largest consumer products companies in the world.
The combined company would generate volumes of 460m hectoliters, revenue of $36.4bn and EBITDA of $10.7bn.
The company will make St Louis in Missouri its North American HQ and home of Budweiser beer.
All of Anheuser-Busch's breweries will remain open. InBev CEO Carlos Brito will be chief executive officer of the combined company.
The board of directors of the combined company will be comprised of the existing directors of the InBev board, Anheuser-Busch president and chief executive August Busch IV and one other current or former director from the Anheuser-Busch board.
Anheuser-Busch will become a wholly owned subsidiary of InBev upon completion of the deal.
"We are very pleased to announce this historic transaction today, bringing together two great companies that share a rich history of brewing traditions," said InBev chief executive Carlos Britto.
"We are extremely excited about the opportunities that this combination will create for consumers worldwide, as well as our shareholders, employees, business partners and wholesalers. Together, Anheuser-Busch and InBev will be able to accomplish much more than each can on its own.
"We have been successful business partners for quite some time, and this is the natural next step for us in an increasingly competitive global environment.
"This combination will create a stronger, more competitive global company with an unrivaled worldwide brand portfolio and distribution network, with great potential for growth all over the world."
August Busch IV, Anheuser-Busch president and chief executive, added: "Today's announcement brings new opportunities for Anheuser-Busch and its business, brands and employees.
"This agreement provides additional and certain value for Anheuser-Busch shareholders, while enhancing global market access for Budweiser, one of America's true iconic brands.
"We will leverage our collective strengths to create a truly diversified, global company to sustain long-term growth and profitability. In the United States and Canada, both InBev and Anheuser-Busch have seen significant benefits from our existing relationship and we look forward to replicating this success in other parts of the world."