The deal will stop 58 stores from closing and protect more than 300 jobs, with EE rebranding to take place with immediate effect.
EE did not release the locations of the stores it has bought.
Vodafone announced on Friday that it would take over 140 Phones4U shops
The retailer collapsed last week when it failed to reach deals with EE and Vodafone to sell mobile services – contracts it relies on to exist.
EE and Vodafone have since been forced to defend accusations that they orchestrated the collapse of Phones4U.
EE has said its decision to end its relationship with Phones4U was because it wanted to focus on its own retail outlets.
An EE spokeswoman said: "We can confirm that we have agreed with the Phones 4u administrator to purchase 58 stores, safeguarding 359 jobs, subject to court approval."