This paper aims to gain insight into (Spanish) tourists' multilingual experiences by analyzing spontaneously written online travel diaries. Using the conceptual framework of Rapport Management Theory (RMT; Spencer-Oatey 2008), I analyze reports on the tourists' mother tongue, local languages, and English as lingua franca in order to examine the relations between language choice and the three interactional principles distinguished in RMT: interactional goals, face concerns, and sociality rights concerns. The data suggests that using one language rather than another may have different implications. Spanish tourists assign a privileged role to their mother tongue, especially for realizing interpersonal goals. Furthermore, tourists regularly describe low English proficiency as a potentially face-threatening characteristic of their own ethnolinguistic group. Finally, Spanish tourists do not seem to consider services in their mother tongue as a commercial right, except in specific contexts where the absence of Spanish language contrasts with other contextual features. On a methodological level, this study seeks to explore the potential of analyzing spontaneously written online diaries as a source of information for sociolinguistic research on multilingualism.