Previous experience with a voice can help listeners understand speech when a competing talker is present. Using the coordinate-response measure task (Bolia, Nelson, Ericson, & Simpson, 2000), Johnsrude et al. (2013) demonstrated that speech is more intelligible when either the target or competing (masking) talker is a long-term spouse than when both talkers are unfamiliar (termed familiar-target and familiar-masker benefits, respectively). To better understand how familiarity improves intelligibility, we measured the familiar-target and familiar-masker benefits in older and younger spouses using a more challenging matrix task, and compared the benefits listeners gain from spouses' and friends' voices. On each trial, participants heard two sentences from the Boston University Gerald (Kidd, Best, & Mason, 2008) corpus ("<name> <verb> <number> <adjective> <noun>") and reported words from the sentence beginning with a target name word. A familiar-masker benefit was not observed, but all groups showed a robust familiar-target benefit and its magnitude did not differ between spouses and friends. The familiar-target benefit was not influenced by relationship length (in the range of 1.5-52 years). Together, these results imply that the familiar-target benefit can develop from various types of relationships and has already reached a plateau around 1.5 years after meeting a new friend. (PsycInfo Database Record (c) 2020 APA, all rights reserved).