A programmable (multistep) resistor attenuator architecture (such as for input to a differential amplifier) provides cancellation for harmonic distortion currents. An attenuation node is coupled: (a) to an input node through R; (b) to a virtual ground through kR and a virtual ground switch Swf with on-resistance Rswf; and (c) to a differential ground through mR and a differential ground switch Swp with on-resistance Rswp. Swp can be sized relative to Swf such that a component Ipnf of Ipn through Rswp and mR to the attenuation node, and branching into kR and Rswf, matches (phase/magnitude), a harmonic current Ifn from the virtual ground through Rswf and kR to the attenuation node. Harmonic distortion cancelation at the virtual ground can be based on matching switches Swf and Swp and the resistors R, mR, kR, reducing sensitivity to PVT variations, input frequency and amplitude. The attenuator architecture is extendable to multistage configurations.