We report on a perimeter-gated single-photon avalanche diode (pg-SPAD) imager fabricated in a 0.35 µm CMOS process. The imager had 4,096 pixels disposed in a two-dimensional array (64 × 64) and peripheral circuitry for pixel access and readout. We demonstrate that the room temperature probability of a dark count occurring at a single pixel vanishes when perimeter gating is used. We further demonstrate that the array-wide noise variance decreases exponentially with an increase in perimeter gate voltage magnitude. The proposed imager architecture lays the foundation for single-photon imaging with negligible dark signal non-uniformity (DSNU).