Application and assessment procedure

Companies will use electronic submission tools to apply for the chemical similarity check. Applications are submitted to ECHA through R4BP 3 as a IUCLID file. For joint applications, one of the applicants should first contact ECHA through the ECHA Helpdesk to receive the joint application number.

This graph shows an overview of the application procedure for chemical similarity check


The application process has several steps. Each step needs to be completed before the application can move to the next step. It is important that the applicant makes sure that all applicable deadlines are met, otherwise the application will be rejected during the course of the process.



Joint application: one of the applicants contacts ECHA to receive the joint application number.


Individual application: The applicant submits the application through R4BP 3.

Joint application: All applicants submit their applications.


ECHA checks that the application and data have been submitted in the correct format and sends the charges invoice through R4BP 3.


The applicant pays the related charges to ECHA within 30 days from the invoice date.


ECHA accepts the application and starts to assess the chemical similarity.


If additional information is needed to carry out the assessment, ECHA will ask for the missing information from the applicant. At the same time, ECHA will specify a time limit for the applicant to submit this information.


The applicant has 15 days to comment the outcome of the assessment.


ECHA will issue the final outcome.



The main actors in the dossier submission process are:


Applicants have the responsibility to provide dossiers with all relevant information related to the chemical similarity check and to provide additional information if requested by ECHA. Applicants are responsible for the quality of the data in their dossiers.


ECHA is responsible for ensuring that the information in the dossiers is in a correct format. ECHA also carries out the assessment of the chemical similarity check and makes sure that the submission process proceeds within the target timelines.