| OAL | Oriental Aromatics Limited | 343.8 | 337.5 | 340.3 | 3.8K | 0.1 | | 0.01 | |
| OBCL | Orissa Bengal Carrier Limited | 55.19 | 54.02 | 54.42 | 9.3K | -0.50 | | 0.91 | |
| ODIGMA | ODIGMA CONSULTANCY SOLUTIONS LTD | 35.99 | 34.25 | 34.94 | 20.6K | -0.79 | | 2.21 | |
| OFSS | Oracle Financial Services | 8,372 | 8,165 | 8,333 | 145.0K | 156 | | 1.90 | |
| OILCOUNTUB | Oil Country Tubular Limited | 64.30 | 60.56 | 62.54 | 24.1K | -1.15 | | 1.81 | |
| OLAELEC | Ola Electric Mobility Ltd | 42.48 | 41.85 | 41.95 | 6.01M | -0.18 | | 0.43 | |
| OLECTRA | Olectra Greentech Limited | 1,403 | 1,365 | 1,387 | 278.3K | 6 | | 0.44 | |
| OMKARCHEM | Omkar Speciality Chemicals Limited | 5.250 | 5.080 | 5.150 | 2.4K | -0.200 | | 3.74 | |
| ONELIFECAP | Onelife Capital Advisors Limited | 13.15 | 12.45 | 12.73 | 10.7K | 0.03 | | 0.24 | |
| ONEPOINT | One Point One Solutions Limited | 56.01 | 54.00 | 55.26 | 2.26M | 0.71 | | 1.30 | |
| ONESOURCE | ONESOURCE SPECIALTY PHARMA LTD | 1,715 | 1,688 | 1,703 | 87.9K | -22 | | 1.28 | |
| ONGC | Oil & Natural Gas Corporation Limited | 250.3 | 245.4 | 249.0 | 7.07M | 2.1 | | 0.83 | |
| ONWARDTEC | Onward Technologies Limited | 290.2 | 283.5 | 285.1 | 68.2K | -1.6 | | 0.54 | |
| OPTIEMUS | Optiemus Infracom Limited | 586.4 | 570.2 | 581.6 | 94.9K | -2.6 | | 0.44 | |
| ORICONENT | Oricon Enterprises Limited | 58.95 | 57.12 | 58.09 | 218.0K | -0.05 | | 0.09 | |
| ORIENTPPR | Orient Paper & Industries Limited | 24.22 | 23.85 | 24.16 | 129.2K | 0.10 | | 0.42 | |
| ORIENTTECH | Orient Technologies Limited | 376.8 | 365.0 | 366.4 | 339.3K | -4.2 | | 1.13 | |
| ORISSAMINE | The Orissa Minerals Development | 5,160 | 5,042 | 5,116 | 5.1K | 34 | | 0.66 | |
| ORTEL | Ortel Communications Limited | 1.400 | 1.300 | 1.300 | 60.6K | -0.040 | | 2.99 | |
| OSIAHYPER | Osia Hyper Retail Limited | 20.40 | 19.80 | 20.01 | 148.2K | -0.12 | | 0.60 | |
| OSWALSEEDS | ShreeOswal Seeds And Chemicals Limited | 14.20 | 13.41 | 13.78 | 21.5K | -0.05 | | 0.36 | |
| OWAIS | Owais Metal and Mineral Processing Ltd | 415.0 | 385.0 | 389.3 | 60.5K | -19.0 | | 4.65 | |