ABSTRACT.- Phosphorus (P) is needed by soybean plants to form vital molecules like ATP and nucleotides and perform plant functions like photosynthesis and Nitrogen biological fixation at nodules. Because P concentration in the soil solution is naturally low, P fertilization is applied to satisfy soybean requirements in high yielding crops. However, a small portion of added P is readily available to the plants, while most is retained by the soil matrix and eventually made available or lost through erosion and run-off to water bodies, where it promotes eutrophication. Therefore, technologies that enhance P uptake by crops could lead to lower P inputs and outputs from soybean cropping systems, improving sustainability. Priestia megaterium ILBB592 and Bacillus pumilus ILBB44 are two PGPR with P mobilization features that were single formulated as biofertilizers and co-inoculated with Bradyrhizobium elkanii on seeds of soybean Genesis 5602 in two consecutive years in the field, with and without P fertilization. Co-inoculation with ILBB592 improved plant P uptake, along with N and K, with and without P fertilization. Diversity was increased by co-inoculation with ILBB44 and ILBB592, and predicted genes related with P cycling in the rhizospheric soils were also augmented after co-inoculation with ILBB592, mostly with P fertilization. Shoot dry weight and yield were also improved although effect on yield was not statistically significant. P fertilization alone had no effect in the first year but showed some effect on nodules dry weight, P uptake and yield on the second year, suggesting a sufficient P level was obtained after repeated fertilizations. ILBB592 biofertilizer showed a positive effect on most plant parameters, including nodulation and P uptake in both years and both P fertilization regimes and is therefore considered as a useful technology to reduce P fertilization without jeopardizing plant performance.