Wieden & Kennedy London, United London, Leagas Delaney and Miles Calcraft Briginshaw Duffy were all knocked out of the running at an earlier stage.
Yell's direct account, which is held by Proximity, and the yell.com digital business, held by AKQA, were not affected by the review.
Mother's appointment ends a mammoth seven-month process, which kicked off after Yell ended its two-decade relationship with Abbott Mead Vickers BBDO. The business went up for pitch in April owing to conflict with AMV's BT client, which is entering the classified directory market.
The pitch was thrown into confusion in July, when the Yell chief marketing officer, Ann Francke, left the company suddenly. Her role was filled temporarily by the Yell head of marketing and strategy, Catherine Kehoe.
Francke was previously the marketing director at Boots, a position she held for just eight months before she was ousted in a management restructure, again in the middle of a pitch.
Last month, Yell named Helen Stevenson, the former Lloyds TSB marketing head, as Francke's replacement.
Neither Mother nor Yell were available for comment.
Comment, page 40
During its 23 years on the Yell account, AMV created a number of celebrated commercials for the brand, including the famous TV spot about "JR Hartley", who uses the Yellow Pages directory to find a copy of his book, "Fly Fishing".
More recent work from AMV included a campaign fronted by the Cold Feet star James Nesbitt.
Neither Mother nor Yell were available for comment.
Comment, page 40.