| Institute | Status | Country | |
|---|---|---|---|
| PTB | Physikalisch-Technische Bundesanstalt | Internal Funded | Germany |
| CEM | Centro Español de Metrología | Internal Funded | Spain |
| CMI | Cesky Metrologicky Institut Brno | Internal Funded | Czech Republic |
| INRIM | Istituto Nazionale di Ricerca Metrologica | Internal Funded | Italy |
| JV | Justervesenet | Internal Funded | Norway |
| NPL | NPL Management Limited | Internal Funded | United Kingdom |
| RISE | Sveriges Tekniska Forskningsinstitut AB | Internal Funded | Sweden |
| TUBITAK | Turkiye Bilimsel ve Teknolojik Arastirma Kurumu | Internal Funded | Turkey |
| VSL | VSL B.V. | Internal Funded | Netherlands |
| VTT | Teknologian tutkimuskeskus VTT Oy | Internal Funded | Finland |
| APPLICOS | Apllicos B.V. | External Funded | Netherlands |
| esz | esz AG calibration & metrology | External Funded | Germany |
| USN | University of South-East Norway | External Funded | Norway |
| INTI | Instituto Nacional de Tecnología Industrial | External Funded | Argentina |
| SC | Signal Conversion Ltd | External Funded | United Kingdom |
| METAS | Eidgenössisches Institut für Metrologie METAS | Unfunded | Switzerland |
| Institute | Country | |
|---|---|---|
| VNIIM | D.I. Mendeleev All-Russian Institute for Metrology | Russia |
| Left-Right d.d.o. | Slovenia |