A handful of second language (L2) studies have explored "bidirectional pragmatic transfer": "forward pragmatic transfer"--the influence of learners' first language (L1) on their L2--and "reverse pragmatic transfer"--the impact of learners' L2 on their L1. This explanatory sequential mixed-methods study investigated how L2 proficiency influenced the bidirectionality of pragmatic transfer in compliment responses. Thirty-four intermediate English-as-a-foreign-language (EFL) learners and 34 advanced EFL learners were recruited from a university in China. The results of computer-mediated communication via WeChat showed that, similar to L1 Chinese speakers, the intermediate learners tended to deny compliments in English, indicating forward pragmatic transfer. Like L1 English speakers, the advanced learners frequently accepted compliments in Chinese, suggesting reverse pragmatic transfer. Furthermore, when responding to compliments in Chinese or English, some advanced learners preferred to accept compliments first and then deny them. Findings from interviews revealed that identity and language prestige might affect bidirectional pragmatic transfer.