Abstract: Although lowest price guarantees (LPGs) are common on airlines’ official websites, a deeper understanding of how customers evaluate these guarantees is lacking. This study examines the effects of two LPG terms—depth of refund and refund conditions—on customer perceptions and purchase intention. An experiment with a 2 × 2 factorial design was conducted with a sample of 282 adults, and structural equation modelling was used to test the model. The results show that refund depth increases customer purchase intention by enhancing perceptions of the believability and value of the LPG. Strict refund conditions enhance customer purchase intention by increasing the believability of the LPGs.