The continuous growth of RFID technology due to the increasing demands of healthcare and manufacturing industries has prompted the assimilation of novel materials for achieving desirable features in RFID identifiers. This paper describes a 920 MHz UHF RFID identifier (tag) antenna, fabricated by drop-casting of MXene (Ti3C2Tx) on acetate substrates at ambient conditions. RFID tags with similar geometries and altered MXene layer thicknesses (0.4 µm and 0.85 µm) were fabricated and experimentally investigated by measuring the input impedance (and reflection coefficients). At 920 MHz, tags with one and two coating cycles demonstrated an input impedance of Z11=73+j105, and Z11=27+j54, respectively. MXene’s drop casting and drying cycles were observed to significantly impact the input impedance of the tags, due to the variation of bulk conductivity in the traces. Additionally, the performance of the tags was monitored upon their operation under cyclic relative humidity levels from 5% to 65%, demonstrating a negligible 0.48% performance fluctuation. The initial findings suggest that drop-casting of MXene on flexible substrates has the potential to produce cost-effective and flexible RFID tags and serve as a viable substitute for conventional metallic tags.