| Short Name | General Description |
| Amdek | |
| Analytical Products | |
| Apogee | |
| Ashton-Tate | |
| BUSS | publication |
| C.D.R. Systems | |
| Cleveland Codonics, Inc | |
| Commsoft | |
| Custom | Entry for user designed/installed custom modifications, experimental or one-off items |
| DG | |
| Evryware | Created several Graphical games for the H89 under both HDOS and CP/M operating systems |
| FBE Research | |
| Heath | Started as an aircraft company about 1900, successfully moved into electronics about 1945. Currently operating as Heathikit Educational Systems, a branch of the original company that survived the various sales and reorgainzations of the larger company. |
| Hoyle & Holye Software | |
| HUG | |
| Kres Engineering | |
| Lifeboat Associates | |
| Magnolia Microsystems | |
| Mako Data Products | |
| Microsoft | |
| Newline Software | |
| NOGDS | Offered add-on cards for the the H8 & H89 which provided graphics, sound, and additional I/O ports |
| Northwest Digital | |
| Peachtree | |
| Percom | Provide peripherals for many 8-bit systems |
| Quikdata | |
| SEBHC | Dedicated to Heath 8 bit computers - H8, H89, ET trainers and half the H/Z-100. We maintain a closed archive of documentation and software. Membership and archive access requires moderator approval. |
| Seimens | |
| Sigmasoft & Systems | |
| Software Toolworks | |
| Software Wizardry, Inc. | |
| Sorcim | |
| Sunflower Software | |
| Tandon | |
| TMSI | Several hardware items (including replacement ROMS) and software utilities for H89 and H-1000 |
| Trionyx | |
| Ultimeth | |
| Visigroup | |
| ZDS | |
| Zilog | A Global Supplier of Innovative Embedded Control Solutions |