Gradient‐index antireflecting surfaces produced by neutral solution processing have a median surface damage threshold of 12 J/cm2for 1‐ns, 1064‐nm pulses. We have found that the threshold can be increased to 25 J/cm2by irradiating the surface with 1064‐nm wavelength pulses with fluence below the initial 12‐J/cm2threshold. Damage thresholds, both before and after this treatment, increased as the square root of the pulse duration in the 1–20‐ns range.