| 3540 | Asphalt brick siding manufacturing | |
| 3540 | Asphalt fibrous plastic roof cement manufacturing | |
| 3540 | Asphalt floor tile manufacturing | |
| 3540 | Asphalt manufacturing | |
| 2909 | Asphalt mining | |
| 3540 | Asphalt paving material manufacturing | |
| 3540 | Asphalt roof cement manufacturing | |
| 3540 | Asphalt roof coating, liquid, manufacturing | |
| 3540 | Asphalt roofing felt, built up, manufacturing | |
| 3540 | Asphalt roofing material manufacturing | |
| 3540 | Asphalt roofing roll manufacturing | |
| 3540 | Asphalt saturated building paper manufacturing | |
| 3540 | Asphalt saturated roofing felt manufacturing | |
| 3540 | Asphalt shingle manufacturing | |
| 3219 | Asphalt, felt-base, floor covering, manufacturing | |
| 3540 | Asphaltic material, liquid, manufacturing | |
| 8329 | Assayer, own account | |
| 6100 | Assembling farm product | |
| 9599 | Astrology service | |
| 3903 | Athletic and sporting glove manufacturing | |
| 3903 | Athletic and sporting goods manufacturing | |
| 3220 | Athletic clothing cutting and sewing | |
| 9490 | Athletic club | |
| 9490 | Athletic club grounds operation | |
| 9490 | Athletic exhibition operation | |
| 5000 | Athletic field construction | |
| 3903 | Athletic helmet manufacturing | |
| 3903 | Athletic pad manufacturing | |
| 3420 | Atlas lithographing | |
| 3420 | Atlas printing | |
| 3420 | Atlas publishing | |
| 8321 | Attorney, own account | |
| 6200 | Auctioneering second hand goods, retail | |
| 6100 | Auctioneering second hand goods, wholesale | |
| 6200 | Auctioneering, retail | |
| 6100 | Auctioneering, wholesale | |
| 7200 | Audible reception, communication service operation | |
| 8322 | Auditor, own account | |
| 9490 | Auditorium operation | |
| 9415 | Author, own account | |