The language choice in the advertisement posters carries a significant role in the absence of audio input. The role of advertisements in the landscape of trade and commerce led many studies in different linguistic communities on the form of the language used but nothing over the choice of Bangla-English code-switching. This leads the study to focus primarily on the purposes of code-switching in advertisement posters. From a sociolinguistic perspective this study tried to explore the relationship between language choice in poster advertisements and consumers’ attitudes toward it. In order to have authentic data, all the stakeholders, i.e. sellers, consumers and copywriters, were taken into consideration. Qualitative research methodology was introduced to interview the 29 participants selected by judgment sampling from those stakeholders through three different semi structured questionnaires. The data were analyzed thematically. The results revealed various purposes of Bangla-English code-switching including communication, drawing consumers’ attention, lack of terminologies and many more.