The cuts are expected to come from Verizon's AOL and Yahoo units and represent about 15 percent of the staff at the two units. About 14,000 people work at AOL and Yahoo.
Many of the jobs are in California and some are outside the United States, according to the source, who asked not to be identified because the matter is not yet public.
Yahoo shareholders on Thursday approved the company's sale, according to preliminary results from a shareholder meeting, and it is expected to be completed on Tuesday.
The No. 1 U.S. wireless operator is combining Yahoo's search, email and messenger assets as well as advertising technology tools with its AOL unit, which it bought in 2015 for $4.4 billion. Verizon expects mobile video and advertising to be new sources of revenue outside the oversaturated wireless market.
Verizon shares are down 15 percent this year.
The acquisition marks the end of the line for Yahoo as a standalone company, a storied Web pioneer once valued at more than $100 billion.
Verizon is rebranding AOL and Yahoo as part of a new venture called Oath, led by AOL Chief Executive Officer Tim Armstrong.
Verizon is betting it can use data from more than 200 million unique monthly visitors to Yahoo sites and combine it with data on 150 million unique monthly AOL users and its own user base of over 100 million wireless subscribers to offer more targeted services for advertisers.
The Yahoo deal came after activist investors led by Starboard Value LP lost faith in Yahoo Chief Executive Officer Marissa Mayer, who was hired in 2012, and forced the sale of the company's core assets. Mayer is not expected to remain at Yahoo after the sale is completed.
Yahoo is still one of the largest properties on the internet, with hundreds of millions of customers using its email, finance and sports offerings, and a heavily trafficked home page. In February 2016, Yahoo announced it was cutting 1,600 employees, or 15 percent of its staff.
The deal's closing was delayed as the companies assessed the fallout from two Yahoo data breaches.
Yahoo disclosed in December that data from more than 1 billion user accounts was compromised in August 2013, making it the largest breach in history. This followed a separate disclosure that at least 500 million accounts were affected in a 2014 breach.