This paper offers a linguistic analysis of epigraphic texts originating in the Endovellicus sanctuary, with particular reference to their use of and variation in Latin. As this sanctuary was visited by mostly local pilgrims from Roman times to late antiquity, the aim of the linguistic analysis is to identify linguistic variation in the sanctuary’s votive texts. The paper also demonstrates that differences in the spellings of the name of the god worshipped in the sanctuary may show characteristics of Vulgar Latin. The epigraphic corpus under study shows various Vulgar Latin traits common to other epigraphic texts known in Lusitania in the same period, with examples of the literary influence and high-level use of the Latin language, which may be related to the high social and cultural status of certain worshippers.