GolinHarris and Edelman are set to fight it out for the wide-ranging account, understood to be worth more than £1m in fees.
GolinHarris currently handles the consumer and cor-porate PR for Orange, while Edelman handles trade PR.
Orange is considering having just one agency to manage the combined PR business.
Orange comms director Stuart Jackson said Orange is not looking to invite a third party to pitch as it is satisfied with the work of both agencies.
Pitches will take place in January and a decision is expected in February. Open Road, which handles public affairs for Orange, will not be affected by this review.