| High Solutions | Greater Poland |
| Highcom Sp. z o.o. | Lublin |
| HigoSense Sp. z o.o. | |
| HintMine | Lesser Poland |
| HIT Enterprises | Pomeranian |
| HLG Sp. z.o.o. | Subcarpathian |
| hmmh Poland Sp. z o.o. | |
| HOFU | |
| Holdapp | |
| Home.pl | West Pomeranian |
| HomeDoctor Sp z o.o. | |
| honestmedia.pl | |
| HOQUS Sp. z o.o. | |
| Horyzont Technologie Internetowe | Greater Poland |
| Host Provider | Lower Silesian |
| host4u.pl | Kuyavian-Pomeranian |
| HostBill | Subcarpathian |
| HostingFirmowy.pl | Świętokrzyskie |
| Hotailors | |
| How Are You | |
| HSBC Continental Europe (Spółka Akcyjna) Oddział w Polsce | |
| HSI Sp. z o.o. | Opole |
| Hued.me | |
| Huge Thing | |
| HugeTECH Sp. z o.o. | Subcarpathian |
| Humansoft Sp. z o.o. | Masovian |
| hurtowniaGSM.pl | Lower Silesian |
| Husarion Sp. z o.o. | |
| Husarnet Sp. z o.o. | |
| HUSPI IT Consulting & Development | |
| Hustro | |
| Huuuge Games | |
| Huzar Software | Lower Silesian |
| Hycom | |
| Hygge Software | |
| Hyh | Silesian |
| HypeDev Group Sp. z o.o. | |
| HYS Enterprise | |
| I-NET.PL Sp. J. | Warmian-Masurian |
| i-Robots | |
| I-Systems | |
| i4B Sp. z o.o. | |
| IBC.pl | Greater Poland |
| IBCS Poland | Lesser Poland |
| IC & Partners Poland S.A. | |
| IC Solutions Sp. z o.o. | |
| iCenter | Lower Silesian |
| ICODA | |
| Icon Brand | |
| iCredit Sp. z o.o. | |