We propose a novel origin for the Higgs boson based on the concept of emergence in an Open Effective Field Theory (Open-EFT) framework. The Higgs field is treated as an open quantum system interacting with a critical, dissipative continuum. Its mass and width arise dynamically from the complex self-energy generated by the environment, while the bare mass is strictly set to zero, m0 = 0. Solving the complex pole equation, we obtain a physical Higgs mass mH = 125.2506 GeV and a total width ΓH = 4.09 MeV, in excellent agreement with Standard Model predictions and experimental measurements. The associated Barbieri–Giudice naturalness measure is found to be ∆BG ≃ 4.3%, demonstrating that the electroweak scale emerges without fine-tuning.The residue of the propagator at the pole is predicted to be Z ≃ 0.36, indicating that the Higgs boson is an emergent composite resonance rather than a fundamental particle. This leads to suppressed effective couplings in off-shell production, yielding a characteristic prediction for the ATLAS off-shell signal strength μoff-shell ≃ Z2 ≈ 0.13, consistent with current experimental constraints. Our framework provides a unified, causal, and natural explanation of the Higgs properties and offers concrete, falsifiable predictions for the High-Luminosity LHC.