| ASTRO Systems, Inc. | Maryland |
| Astrobotic Technology | Pennsylvania |
| Astrocyte Pharmaceuticals, Inc. | |
| Astrodyne TDI Power Supplies & EMI Filters | Massachusetts |
| AstroGraph Software, Inc. | California |
| AstroGrowth | Florida |
| Astrolabe Analytics | Washington |
| Astrolabe Diagnostics | Virginia |
| Astrometric Instruments, Inc. | Massachusetts |
| Astron Corporation | California |
| Astron International, Inc. | Texas |
| Astron Solutions | New York |
| Astronics Corporation | New York |
| Astronomer | |
| Astronomic, Inc. | |
| AstroPrint | Connecticut |
| Astroscale U.S., Inc. | |
| Astrox Corporation | |
| Astute Computing, LLC | Vermont |
| Astute Web Group | |
| ASU Research Park | Arizona |
| Asuragen, Inc. | Texas |
| Asure | Texas |
| aSureFit.com | Montana |
| Asurio, Inc. | Colorado |
| Asutin Startup Week | Texas |
| ASY Digital Office | |
| Asylia Therapeutics, Inc. | |
| Asylon, Inc. | |
| Asylum Ventures | |
| Asymchem, Inc. | |
| Asymm | |
| Asymmetrex, LLC | Massachusetts |
| Asymmetric Capital Partners | |
| AsysCode | Illinois |
| At Bags End Web Design | Oregon |
| At Design Studio, Inc. | Massachusetts |
| At Ebc, Inc. | Wisconsin |
| At One Ventures | |
| AT&T | Texas |
| AT&T Business | Texas |
| AT&T Cybersecurity | Texas |
| AT&T Labs | Texas |
| At-Bay, Inc. | |
| ATA RiskStation | Texas |
| ATA Ventures | California |
| Ataboy Studios, Inc. | New York |
| Atacama Therapeutics, Inc. | Massachusetts |
| Ataccama Corporation | New York |
| AtaCor Medical, Inc. | California |