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We compute the complete nonlocal one-loop form factors F1(□/Λ 2) and F2(□/Λ 2 , ξ) of the curvature-squared sector of the spectral action S = Tr f (D 2 /Λ 2) for the full Standard Model particle content: 4 real scalars (Higgs), 45/2 Dirac-equivalent fermions (3 generations), and 12 gauge bosons (SU(3) × SU(2) × U(1)). Using the Barvinsky-Vilkovisky covariant perturbation theory and the Codello-Zanusso diagrammatic heat kernel, we derive closed-form results for each spin sector (0, 1/2, 1) in the {C 2 , R 2 } Weyl basis and assemble the Standard Model totals. The local limits, determined by standard heat kernel coefficients [1, 2], yield αC = 13/120 for the Weyl-squared coefficient and αR(ξ) = 2(ξ − 1/6) 2 for the R 2 coefficient, where ξ is the Higgs non-minimal coupling. Both form factors are shown to be entire functions of □/Λ 2 , ensuring that the one-loop effective action introduces no additional propagator poles beyond those of the classical theory. We derive the c1/c2 ratio in the {R 2 , R 2 µν } basis, the scalar graviton decoupling condition at conformal coupling ξ = 1/6, and the UV asymptotic behavior. The form factors yield a modified Newtonian potential with calculable effective masses m2 = Λ √ 60/13 and m0 = Λ/ √ 6(ξ − 1/6) 2 , connecting the spectral action framework to solar-system phenomenology. All results are verified by independent multi-precision numerical evaluation.