Multiphoton ionization driven by combined midinfrared (MIR) and vacuum-ultraviolet (VUV) fields can proceed efficiently even when the VUV photon energy lies below the ionization threshold, provided that additional MIR photons bridge the energy gap. When using a few-cycle MIR pulse, its large bandwidth enables a two-color regime in which two distinct ionization pathways, which differ by one absorbed MIR photon, reach the same final photoelectron energy and therefore interfere coherently. Using the hydrogen atom as an example and solving the time-dependent Schrödinger equation in the combined fields, we show that the total ionization yield exhibits a pronounced phase-delay dependence, oscillating twice per MIR optical cycle as the relative VUV-MIR phase is varied. This subcycle modulation is a direct signature of interference between the competing multiphoton pathways. In an orthogonal-field geometry, the same pathway interference imprints a strong, phase-dependent modulation on the low-energy photoelectron momentum distribution, enabling substantial redistribution and redirection of emitted photoelectrons. These results establish a different coherent-control scheme for steering photoelectrons via interference of multiphoton pathways in two-color strong-field ionization, and provide a simple platform for extending phase-controlled electron shaping to more complex targets.

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• Atomic & molecular processes in external fields
• Coherent control
• Multiphoton or tunneling ionization & excitation
• Single- and few-photon ionization & excitation