One of the renowned industries which provides services to the community is the delivery courier services – these are businesses which facilitate the transport and delivery of documents and packages. Along with the expansion of E-commerce, the demand for delivery courier services has also increased. Primarily, during the pandemic where community restrictions are imposed, these services are observed to have surge in demands because of the emergence of online purchasing. Delivery services have been convenient and necessary for businesses and individuals hence the said industry has been important for countries like the Philippines. The present study aims to make use and capitalize the tool Decision theory/analysis in choosing which courier in the Philippines is the much preferred by the customers. Through a preliminary survey the researchers were able to gather the most widely used courier by the customers namely: J&T Express, Lalamove and Grab Express. The results obtained from the study shows that in the Maximax Criterion the best decision was Grab Express, in the Maximin Criterion J&T Express was the best decision, in the Minimax Criterion J&T Express was the best decision, in the Hurwicz Criterion J&T Express was the best decision, and in the Equal Likelihood Criterion J&T Express was the best decision. Resulting that J&T Express was the optimal delivery courier service from the data gathered by the researchers.