| no. | Participant Type | Short Name | Organisation legal full name | Country |
| 1 | Internal Funded Partner | INRIM | Istituto Nazionale di Ricerca Metrologica | Italy |
| 2 | Internal Funded Partner | Aalto | Aalto-korkeakoulusäätiö sr | Finland |
| 3 | Internal Funded Partner | CMI | Cesky Metrologicky Institut | Czech Republic |
| 4 | Internal Funded Partner | DFM | Dansk Fundamental Metrologi A/S | Denmark |
| 5 | Internal Funded Partner | PTB | Physikalisch-Technische Bundesanstalt | Germany |
| 6 | Internal Funded Partner | TUBITAK | Turkiye Bilimsel ve Teknolojik Arastirma Kurumu | Turkey |
| 7 | External Funded Partner | DTU | Danmarks Tekniske Universitet | Denmark |
| 8 | External Funded Partner | ENS Paris‑Saclay | Ecole Normale Supérieure Paris-Saclay | France |
| 9 | External Funded Partner | Qnami | Qnami AG | Switzerland |
| 10 | External Funded Partner | SQ | Sparrow Quantum A/S | Denmark |
| 11 | External Funded Partner | Thales | THALES | France |
| 12 | External Funded Partner | UNITO | Università degli Studi di Torino | Italy |