Malnutrition is a global health problem, which can be managed through biofortification. Bioaugmentation of Zn solubilizing rhizobacteria could be a sustainable intervention to increase bioavailability of Zn in soil, which can be helpful in mitigation of yield loss and malnutrition of zinc accompanied by various mechanisms including biological N2 fixation, nutrient solubilization, siderophores, hydrogen cyanide, ammonia and indole-3-acetic acid (IAA) production, 1-aminocyclopropane-1-carboxylate (ACC) deaminase and antifungal activities are important for plant stress amelioration. In the present study, a number of pure rhizobacterial colonies were isolated from maize rhizosphere and screened for their ability to solubilize zinc oxide. These isolates were screened on the basis of zinc and phosphate solubilization, IAA production, protease production, catalase activity along with other traits. All the selected isolates were also positive for oxidase activity (except ZM22), hydrogen cyanide (HCN) production and utilization of citrate. More than 70% of isolates produced ammonia, hydrogen cyanide, siderophores, exopolysaccharides, and cellulase. More than half of isolates also showed potential for urease activity and production of lipase. The ZM31 and S10 were the only isolates, which showed the chitinase activity. All of these isolates were evaluated in a jar trial for their ability to promote the growth of maize seedlings. Results revealed that inoculation of selected zinc solubilizing rhizobacterial isolates improved the growth of maize. In comparison, isolates ZM20, ZM31, ZM63 and S10 were best compared to other tested isolates in stimulating the growth attributes of maize like shoot length, root length, plant fresh and dry biomass. These strains were identified as Bacillus sp. (ZM20), Bacillus aryabhattai (ZM31 and S10) and Bacillus subtilis (ZM63) through 16S rRNA sequencing. The identified strains having multi-growth promoting attributes and ability to promote the growth of maize as evaluated in the previous steps shown to be gram positive. The results of the root colonization assay revealed that all the strains showed their ability to colonized roots but the maximum root colonization ability was shown by strain Bacillus sp. (ZM20). The top four most promising ZSB strains were selected for further evaluation in pot and field trials. The results of pot and field trials revealed that zinc solubilizing strains significantly improved the activity of antioxidant enzymes, plant growth and yield attributes of maize. The strains also improved the accumulation of macro and micronutrients in different parts of plant and successfully biofortified the maize grains with Fe and Zn. More biofortified minerals contents in grains were obtained from co-inoculations treatments. Among co-inoculation treatments, Bacillus aryabhattai (ZM31) × Bacillus subtilis (ZM63) demonstrated best results in all observed attributes. The co-inoculation of these strains could be a novel biofortification intervention for remedy of zinc in plants. Zinc solubilization activity of Bacillus spp. strains was associated with drop in pH due to production of organic acids. The Ultra Performance Liquid Chromatography (UPLC) and Gas chromatography-mass spectrometry (GC-MS) analysis reported seven kinds of organic acids, i.e. lactic, acetic, citric, succinic, formic, isobutyric and isovaleric acids from the cultures. Main acids produced were lactic acid and acetic acid, with isobutyric acid and isovaleric acid as relatively minor but important acids in Bacillus sp. (ZM20) and Bacillus subtilis (ZM63). Such bacteria could be very effective as bio-inoculants to improve growth, and yield of maize under nutrient deficient soil conditions and also for biofortification of minerals in cereals for human consumption to overcome the problems of malnutrition.