An organic-based multi-layered phased-array antenna package for a 28GHz 5G radio access applications is hereby introduced. The package incorporates 64 dual-polarized antenna elements and features an air cavity common to all antennas. Direct antenna probing measurements of the package show over 3GHz bandwidth and 3dBi gain at 28GHz. A phased array transceiver module has been developed with the package and four SiGe BiCMOS ICs are attached using flip-chip assembly. Module-level measurements in TX mode show 54dBm EIRP and near-ideal 35dB gain increase for 64-element power combining. 64-element radiation pattern measurements are reported with a steering range of > ±40 degrees without tapering in off-boresight direction.