| Company name | Reg. code |
|---|---|
| ESTRON HOLDING OÜ (former name Estron Holding UÜ) | 14715932 |
| ESTRAVEL HOLDING OÜ (former name ESTRAV HOLDING OÜ) | 12967500 |
| ASTRAN HOLDING OÜ | 10893513 |
| ESTELON HOLDING OÜ | 17193575 |
| ASTRON INTERNATIONAL GLOBAL HOLDING OÜ | 14693478 |
| MULTIINVEST OÜ kustutatud (former name ESTFIN WELDING OÜ) | 11412852 |