This article presents three studies focusing on the impact of procedural fairness resulting from a tax official’s behavior on acceptance of tax authority decisions and intention to appeal in the context of gain and loss frames. The studies were conducted using 588 participants recruited from an online panel (computer-assisted Web interview). In all studies, we introduced a procedural fairness factor. Study 1 manipulated tax frame (gain vs. loss); Study 2, three different extents of loss (small, moderate, and large); and Study 3, three different extents of gain (small, moderate, and large). The results of all three studies demonstrated the significant role of procedural tax fairness. Moreover, Study 1 showed a significant impact of tax frame and Study 2 revealed a significant role of the extent of a tax loss. Study 3, however, found no impact of the extent of a gain on decision acceptance and intention to appeal. Participants accepted all gains and were not willing to appeal against a favorable decision. (PsycINFO Database Record (c) 2019 APA, all rights reserved)