| OBCL | Orissa Bengal Carrier Limited | 56.89 | 55.00 | 56.03 | 26.7K | 0.35 | | 0.63 | |
| ODIGMA | ODIGMA CONSULTANCY SOLUTIONS LTD | 37.00 | 35.60 | 36.06 | 29.4K | -0.72 | | 1.96 | |
| OFSS | Oracle Financial Services | 8,296 | 8,159 | 8,224 | 71.2K | -80 | | 0.96 | |
| OILCOUNTUB | Oil Country Tubular Limited | 64.69 | 63.22 | 63.85 | 14.6K | 0.40 | | 0.63 | |
| OLAELEC | Ola Electric Mobility Ltd | 42.90 | 41.80 | 42.29 | 7.01M | 0.09 | | 0.21 | |
| OLECTRA | Olectra Greentech Limited | 1,430 | 1,396 | 1,407 | 252.6K | -14 | | 1.00 | |
| OMKARCHEM | Omkar Speciality Chemicals Limited | 5.580 | 5.100 | 5.490 | 9.7K | 0.170 | | 3.20 | |
| ONELIFECAP | Onelife Capital Advisors Limited | 13.88 | 13.00 | 13.53 | 22.6K | -0.15 | | 1.10 | |
| ONEPOINT | One Point One Solutions Limited | 52.41 | 50.82 | 51.65 | 788.3K | 0.16 | | 0.31 | |
| ONESOURCE | ONESOURCE SPECIALTY PHARMA LTD | 1,740 | 1,719 | 1,732 | 121.8K | 6 | | 0.35 | |
| ONGC | Oil & Natural Gas Corporation Limited | 249.7 | 245.1 | 247.6 | 9.18M | -3.3 | | 1.30 | |
| ONWARDTEC | Onward Technologies Limited | 288.8 | 283.2 | 286.1 | 9.9K | 1.9 | | 0.65 | |
| OPTIEMUS | Optiemus Infracom Limited | 576.4 | 551.2 | 557.4 | 94.7K | -14.0 | | 2.44 | |
| ORICONENT | Oricon Enterprises Limited | 58.61 | 57.24 | 58.01 | 297.2K | -0.46 | | 0.79 | |
| ORIENTPPR | Orient Paper & Industries Limited | 25.05 | 24.20 | 24.40 | 414.8K | -0.77 | | 3.06 | |
| ORIENTTECH | Orient Technologies Limited | 391.3 | 377.2 | 382.3 | 348.4K | -1.1 | | 0.27 | |
| ORISSAMINE | The Orissa Minerals Development | 5,221 | 5,090 | 5,117 | 5.1K | -75 | | 1.44 | |
| ORTEL | Ortel Communications Limited | 1.350 | 1.220 | 1.220 | 16.2K | -0.070 | | 5.43 | |
| OSIAHYPER | Osia Hyper Retail Limited | 20.97 | 20.23 | 20.38 | 158.8K | -0.32 | | 1.55 | |
| OSWALSEEDS | ShreeOswal Seeds And Chemicals Limited | 14.68 | 14.11 | 14.30 | 42.8K | -0.38 | | 2.59 | |
| OWAIS | Owais Metal and Mineral Processing Ltd | 471.0 | 450.0 | 457.6 | 16.5K | -7.9 | | 1.69 | |