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A sound prediction of soil organic phosphorus (P o ) mineralization would be helpful to improve fertilizer recommendations. However, in most mineral soils expensive and time consuming isotopic dilution experiments are required to assess P o mineralization. A proposed method to estimate P o mineralization is the quantification of P in the coarse fraction (CF, >53 μm) of the soil. The aim of this study was to evaluate if P in the CF can effectively predict P o mineralization. Soil samples from three North American long-term arable field experiments (>10 years) with different textures (sand content 15–82%) and different fertilization treatments (non-P-fertilized, mineral P fertilizer, poultry litter) were analyzed. Soil samples were physically fractioned into CF and fine fraction (FF, <53 μm). Total P (P t ), P o , and total carbon (C t ) were determined in each fraction. Gross and net P o mineralization rates as well as soil respiration were determined in a 13-day-incubation experiment. The cumulative gross P o mineralization over 13 days ranged from 8.3 to 38.6 mg P kg −1 , while P t in CF varied between 9.7 and 90.7 mg P kg −1 and P o in CF between 6.1 and 17.7 mg kg −1 . No association between P t in CF and gross or net mineralized P o was observed. However, a significant linear relationship between P o in CF and net (R 2 :0.68, p < 0.01) and gross mineralized P o (R 2 :0.72, p < 0.01) was observed after 6 days and 13 days of incubation. Additionally, gross and net mineralized P o could also be predicted from C respiration, and these models were significantly improved by incorporating the C t :P o ratio of the CF. Our results suggest that the quantification of P o in the CF as well as the measurement of respiration corrected by the C t :P o ratio of the CF are promising non-isotopic indicators of P o mineralization rates. [ABSTRACT FROM AUTHOR]