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Continually land‐applying manure at rates exceeding crop removal can change soil P chemistry and increase soil P to levels that are of environmental concern. To assess the effect of long‐term manure application on soil P forms and solubilities, we determined water‐extractable P, Mehlich‐3 P, Hedley‐P fractions, and crystalline Ca‐P minerals in surface soil (0–5 cm) from 20 locations in New York (n = 6), Oklahoma (n = 8), and Pennsylvania (n = 6), which received dairy, poultry, or swine manure (40–200 kg ha⁻¹ yr⁻¹) for 10 to 25 yr. For all untreated and manured soils, the pH averaged 5.9 and 6.6; exchangeable Ca, 0.9 and 6.2 g kg⁻¹; organic C, 15.7 and 32.6 g kg⁻¹; and total P, 407 and 2480 mg kg⁻¹, respectively. As Mehlich‐3 P increased (64–2822 mg kg⁻¹), the proportion that was water extractable (14–3%) declined as exchangeable soil Ca increased (R² = 0.81). Results suggest that addition of manure …