The present study adopted a socio-pragmatic approach to contribute to the broader literature on code-switching (CS) in bilingual communication by exploring its role in the context of speech act negotiations. Specifically, it explores 107 instances of CS from English to Arabic by nine Saudi female speakers of English as a Foreign Language (EFL) during interactions with a British native speaker during offer interactions in an informal context. Conversations were recorded during a dinner attended by three friends. The number of times women switched from English into Arabic, the position of CS within the offer interaction, and its type and function were quantified. The study revealed that CS was frequent, aligning with sociolinguistic findings indicating that even proficient bilinguals use CS conversationally. The findings reveal nuanced preferences, patterns, and functions associated with CS in this particular social activity. The participants strategically used CS during offer negotiations, often favouring turn-switching in a non-sequential manner. The primary function of CS was the expression of feelings, frequently involving appreciative expressions and preferences. In addition, participants used CS to emphasise points and invoke God, reflecting cultural and religious influences on language choice. Overall, CS serves as a tool for effective communication, offering insights into the speaker's identity and cultural background.