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Abstract Inorganic salts present in the atmosphere may affect the composition and abundance of secondary organic aerosol. Here, we quantify the effects of salt identity, salt concentration (ionic strength), and solution pH on the partitioning of ambient water‐soluble organic gases (WSOC_g) at a site in the eastern United States. The experimental pH (pH = 1–6) and ionic strengths (10⁻³–10¹ mol kg⁻¹) span a wide range of conditions found in atmospheric particles, clouds, and fog droplets. Chloride salts (NaCl, NH₄Cl, and KCl) exhibit a strong salting‐out effect at all ionic strengths >0.005 mol kg⁻¹and pH = 1.8–6. In contrast, sulfate salts (Na₂SO₄, (NH₄)₂SO₄, and K₂SO₄) induce both salting‐in and salting‐out behaviors, depending on ionic strength and pH. These results suggest that monovalent cations have minimal effect, while ionic strength, pH, and anion identity exert strong effects on the partitioning of ambient organic gases in the atmosphere.