A resonator based metamaterial for sensor application is studied in this paper. The resonator is encompassed by a partial ground plane and excited by a microstrip feed‐line. As the resonator, partial ground frame, and the feeding transmission line are on the same microstrip, the measurement can be executed by using the common laboratory facility instead of using the waveguide. The proposed metamaterial occupies a compact size of 20 × 20 mm2 and is imprinted on a low‐cost FR4 substrate. The substrate has a relative permittivity of 4.6 with a dielectric loss tangent of 0.02. The resonator and the ground frame are placed on the similar part of the substrate and the feed‐line is placed on the other part of the substrate. In metamaterial design, normally arrays of metamaterial unit cells are needed, whereas this study presents only one cell, which can achieve the metamaterial properties. The characteristic parameters are fetched and analyzed to find the concurrency between the simulated and measured results. The presented metamaterial is applied in sensor applications where the simulated and measured results reveal considerable agreement.