| 4520 | Quadruplexes, construction | |
| 0122 | Quail farming | |
| 7499 | Quality control (product inspection), service | |
| 7421 | Quantity surveyor services | |
| 7513 | Quarantine services, animal, federal | |
| 4540 | Quarry tile work, installation | |
| 2693 | Quarry tile, clay, manufacturing | |
| 1410 | Quarry, dimension, slate | |
| 1410 | Quarry, dolomite | |
| 1410 | Quarry, granite | |
| 1410 | Quarry, limestone | |
| 1410 | Quarry, marble | |
| 1410 | Quarry, sand and/or gravel | |
| 1410 | Quarry, sandstone | |
| 1410 | Quarry, sedimentary rock | |
| 1410 | Quarry, shale | |
| 2924 | Quarrying machinery and equipment, manufacturing | |
| 5150 | Quarrying machinery and equipment, wholesale | |
| 0121 | Quarter horses, raising | |
| 3430 | Quarter panels, motor vehicle, metal, stamping | |
| 1920 | Quarters (i.e., shoe cut stock), leather, manufacturing | |
| 1429 | Quartz crystal mining (pure) | |
| 3210 | Quartz crystals, electronic applications, manufacturing | |
| 1410 | Quartz sand, crude, mining | |
| 1410 | Quartzite, crushed and broken stone, quarrying | |
| 1410 | Quartzite, crushed or pulverized, mining | |
| 1410 | Quartzite, dimension-quarrying | |
| 1410 | Quartzite, quarrying | |
| 2411 | Quebracho extract, manufacturing | |
| 2411 | Quercitron extract, manufacturing | |
| 1513 | Quick freezing of fruit and vegetables | |
| 2221 | Quick printing (except photocopy service) | |
| 5122 | Quick-frozen foods, packaged, wholesale | |
| 2694 | Quicklime (i.e., calcium oxide), manufacturing | |
| 1320 | Quicksilver (mercury) ore mining | |
| 1320 | Quicksilver mine | |
| 5232 | Quilting materials and supplies, retail | |
| 1729 | Quilting of textiles | |
| 1721 | Quilts, made from purchased materials | |
| 0113 | Quince orchards and farms | |