Prior studies have found that emojis can contribute to rebuilding customers’ trust when after-sale staff apologize to them, but studies on the different types of emojis and their different levels of effectiveness in rebuilding trust are still needed. In this paper, we explore the different types and frequencies of emojis and their effectiveness in rebuilding trust based on commercial discourses. Our data are collected from conversations between after-sale staff and customers during Ali Trademanager after-sale service. We find three types of emojis frequently used when after-sale staff apologizing to customers: face-related emojis, gesture-related emojis, and object-related emojis. Moreover, face-related emojis are the most frequently used, as their nature is to express emotion and attitude. The most effective emojis are the whimper emoji and kiss emoji, which are used by after-sale staff for sajiao (literally, ‘playing cute’). On the other hand, we show that the least effective emojis are the sorry emoji and happy emoji, which are deemed insincere because they violate the quality maxim and quantity maxim in the Cooperative Principle. This paper thus contributes to understanding the nature and function of emojis in commercial communication.