Prior request for information from ECHA

Last update

Under the REACH regulation, all chemical substances manufactured or imported in quantities of one tonne or more per year and falling within its scope of application must be registered with the European CHemicals Agency (ECHA) before being manufactured or placed on the market in the European Economic Area (EEA), i.e. the 27 EU Member States, Iceland, Liechtenstein and Norway.

Companies wishing to register chemical substances are obliged to inquire with ECHA whether the same substance has already been registered before proceeding with their registration.

Potential registrants must therefore submit a prior request for information (inquiry) to ECHA. On the basis of the information received, ECHA determines whether the substance in question has already been registered or if there are other potential registrants for the same substance.

This allows potential registrants to:

  • determine whether a registration was submitted by another registrant for the same substances;
  • inform ECHA of their information needs relative to a given substance;
  • share available data with other registrants or potential registrants of the same substance and work with them to submit a joint registration thereof.

Who is concerned?

As of 1 January 2020, substances that had been pre-registered have had their pre-registration voided. This means that all potential registrants of a substance are concerned by the procedure of prior request for information.


Potential registrants should pay specific attention to the substance identity information they provide to allow unequivocal substance identification.

They are advised to check the ECHA website to see whether the substance is on the list of either pre-registered or registered substances.

How to proceed

Submitting an inquiry

An inquiry file is prepared as follows:

  • by first creating the file using the most recent version of IUCLID;
  • and then submitting it on the REACH-IT platform (IUCLID detects any missing information thanks to its control plug-in and to carry out a prior check of certain "administrative rules").

ECHA's response

Once the inquiry is received, ECHA checks to make sure the file is complete.

Potential registrants need to wait for the result of the inquiry before submitting the registration file or starting any tests on vertebrate animals.

The result of the inquiry may trigger legal obligations to submit a joint registration and share data.

Depending on the information provided in the application files, ECHA directs applicants to the corresponding co-registrant page in REACH-IT, where they can find contact details of other registrants and potential registrants of the same substance.

Online services and forms

Online services

Who to contact

REACH & CLP Helpdesk Luxembourg

European Chemicals Agency (ECHA)

Related procedures and links


Registering a chemical substance (REACH)


Legal references

  • Règlement d'exécution (UE) 2019/1692 du 9 octobre 2019

    concernant l’application de certaines dispositions du règlement (CE) no 1907/2006 du Parlement européen et du Conseil relatives à l’enregistrement et au partage des données après l’expiration du dernier délai d’enregistrement fixé pour les substances bénéficiant d’un régime transitoire

  • Loi du 16 décembre 2011

    concernant l'enregistrement, l'évaluation et l'autorisation des substances chimiques ainsi que la classification, l'étiquetage et l'emballage des substances et mélanges chimiques

  • Règlement (CE) no 1907/2006 du Parlement européen et du Conseil du 18 décembre 2006

    concernant l'enregistrement, l'évaluation et l'autorisation des substances chimiques, ainsi que les restrictions applicables à ces substances (REACH), instituant une agence européenne des produits chimiques, modifiant la directive 1999/45/CE et abrogeant le règlement (CEE) no 793/93 du Conseil et le règlement (CE) no 1488/94 de la Commission ainsi que la directive 76/769/CEE du Conseil et les directives 91/155/CEE, 93/67/CEE, 93/105/CE et 2000/21/CE de la Commission

Your opinion matters to us

Tell us what you think of this page. You can leave us your feedback on how to improve this page. You will not receive a reply to your feedback. Please use the contact form for any specific questions you might have.

Fields marked with an asterisk (*) are mandatory.

Did you find what you were looking for?*
How would you rate this page?*
Very poor
Very good

Leave a comment to help us improve this page. Do not provide any personal information such as your email address, name, telephone number, etc.


Please rate this page

Your opinion has been submitted successfully!

Thank you for your contribution. If you need help or have any questions, please use the contact form.

Would you like to help us make digital public services more user-friendly by submitting your suggestions for improvement?

Then visit Zesumme Vereinfachen, the online participation platform dedicated to administrative simplification in Luxembourg.

Let's simplify things together

An error occurred

Oops, an error has been detected during your form processing.