HSL and SSSL are two endangered sign languages of Hawai'i and Papua New Guinea, respectively. Mouthings of spoken words in signing, especially in smaller sign languages, is a growing topic in sign language linguistics. Here, I present an analysis of mouthings in HSL and SSSL. Mouthings in these languages may present patterns that are previously unattested in other sign languages, both because the scope of existing research on signing is often limited to North America and Europe and because HSL and SSSL are both used in highly multilingual communities. To categorize and compare mouthings in these languages, obligatoriness of manual and non-manual components, linguistic function, and likely source language are analyzed for each mouthing. Findings here suggest that the mouthing patterns in HSL are typologically unusual, while those in SSSL are more like standard mouthings described in previous literature. Multilingual mouthings are found in both HSL and SSSL, with correlations between source languages and mouthings' functions. Incongruencies between the HSL mouthings and those in other languages and potential challenges for outsider researchers in identifying mouthings (and their source languages in multilingual contexts) have broader implications for typologies of mouth actions and research practices.