This Letter reports a 25.80-30.84 GHz wideband millimetre-wave VCO in 65-nm CMOS technology. A 4-bit binary-weighted capacitor bank is used to extend the tuning range. The PMOS current source, as well as the LC noise filtering network, are used to improve the phase-noise performance. Occupying a core area of 0.056 mm(2), the implemented VCO core consumes 4.1 mW at a 1 V supply. At 26 GHz, it achieves a phase noise of -102.8 dBc/Hz at 1 MHz offset.