CAS Registry Services℠

Gain clarity with unique identifiers of chemical substances

CAS Registry Services helps you obtain CAS Registry Numbers® (CAS RNs®), CA Index Names, and substance information for reports, proprietary files, online searching, and regulatory applications.

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Element card for nitrogen: symbol N, atomic number 7, weight 14.007, CAS Registry Number 7727-37-9.

Looking for CAS Registry Numbers or CA Index Names for known substances?

If you’re looking for a unique substance, simply complete and submit a CAS Registry Lookup service order form and receive results within 24 hours (excluding weekends and holidays). The current cost is $75 per substance name or CAS Registry Number searched.

Also available is CAS Common Chemistry, an open community resource with nearly 500,000 chemical substances from CAS REGISTRY®.

CAS Registry Lookup Service order form
Obtain a novel CAS RN or CA Index Name
Substance information for INN or USAN
Substance identification for EPA PMN
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Obtain a CAS Registry Number or CA Index Name for your novel chemical substance with the following steps:

  1. Review the CAS Registration Criteria Overview and Registry Number Info Requirements, as well as the FAQ below.  
  1. Submit a CAS Registry Services consultation request for nomenclature and/or CAS Registry Number assignment and provide the relevant chemical structure diagrams or descriptive information (including a unique substance identifier limited to 20 alphanumeric characters).
Testimonial: CAS Registry Services issued two Registry Numbers in time for an INN application deadline.
Completing a WHO INN or USAN application?

Consult with CAS Registry Services chemists when you need a CAS Registry Number or to find substance information for reports, proprietary files, online searching, confirmation for an International Nonproprietary Name (INN), or United States Adopted Name (USAN) application.

  1. Review the CAS Registration Criteria Overview and Registry Number Info Requirements, as well as the FAQ below.  
  1. Submit a CAS Registry Services consultation request along with relevant chemical structure diagrams or descriptive information (including a unique substance identifier limited to 20 alphanumeric characters).
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Completing an EPA PMN application?

CAS Inventory Expert Services (IES) helps you obtain CA Index Names and CAS Registry Numbers necessary to complete pre-manufacturing notices for EPA TSCA. Your work with CAS IES will remain confidential.  

Follow these steps to ensure a smooth process:

  1. Prepare: Ensure complete chemical identity for Class 1 and Class 2 substances. Review what "What information must be provided for a CAS Inventory Expert Service request?" and other frequently asked questions below.  
  1. Complete forms: Fill out the EPA PMN form and submit it to both the EPA and CAS, or provide the required substance information to CAS.  
  1. Submit request to CAS: Complete the CAS request form, attaching your completed EPA PMN form.
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Want to license CAS REGISTRY data?

Improve your digital R&D workflows and ensure compliance when you license CAS REGISTRY data:

  • Integrate CAS Registry Numbers (CAS RNs) into your digital R&D processes.
  • Ensure your public data meets regulatory standards.
  • Tap into a source with over 275 million unique chemicals.
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CAS Registry Services FAQ

What is CAS Registry Services?

What is CAS REGISTRY?

What experience does the CAS Registry team have?

Will my requests be confidential?

What does CAS Inventory Expert Services cost?

What do other CAS Registry Services cost?

What information must be provided for a CAS Registry Services consultation request?

What information must be provided for a CAS Inventory Expert Service request?

What is the turnaround time for a CAS Registry Services request?

Can I get my results sooner?

How are results delivered?

What if I have questions about my results?