In alignment with the World Marrow Donor Association (WMDA), the NMDP/Be The Match has decommissioned non-GRID identifier formats. When you need to identify a donor, for any purpose, you should only be using GRID as the donor identifier. Best practice is to copy and paste the GRID from a source of truth instead of risking error due to manual entry. As a reminder, ISBT 128 provides a globally unique product identifier, and GRID provides a globally unique unrelated adult donor identifier.

Global Registration Identifier for Donors

  • GRID Frequently Asked Questions for Network Partners / Centers
    Answers questions you may have about the inception of GRID, how NMDP / Be The Match is implementing GRID and what you need to do as a center / partner
  • GRID Readiness Checklist
    A guide for centers / partners to consider multiple inputs for being GRID-ready
    NOTE: this is not an all-inclusive list
  • GRID Traceability Guide
    A guide to show how to use a primary system / paperwork to support traceability
    NOTE: actual placement of GRID may change at system implementation
  • GRID presentation from Council 2018 
    Council presentation deck including details of processes for centers / partners to consider and screenshots of where you could see GRID in systems / labels / paperwork 

What is GRID?

The GRID standard is a 19-character identifier composed of three elements: 

  1. A 4-digit Issuing Organization Number (ION) – The National Marrow Donor Program® (NMDP) / Be The Match® ION is 3553
  2. A 13-character Registration Donor Identifier (RDI) assigned by the issuing organization  
  3. A 2-digit checksum – a calculated number that ensures the preceding 17 digits are accurate and not mistyped

GRID numbers

    *other registries may have capitalized alpha characters in their GRID

    Assignment of GRIDs 

    NMDP / Be The Match assigns a GRID to all donors on the Be The Match Registry. 

    WMDA has mandated that old ID formats be decommissioned by December 15, 2020 when sharing IDs with other registries and partners. You should only be using GRID for all interactions and discussions regarding donor identification. 

    We will follow and promote the GRID Standard as published by ICCBBA and additional implementation details as provided by WMDA. See this ICCBBA webpage for details.

    Final Phase of GRID

    The final phase of GRID starts on December 15, 2020, with all documents and forms completed no later than June 30, 2021.


    • All of our IT systems have been updated to ensure GRID as the donor identifier, including all systems we use to communicate with WMDA and other registries. Please note, we recognize the NMDP DID can never fully disappear for traceability requirements. Because of this, GRID-only could mean the DID has been moved to a less prominent location to align with WMDA requirements.

    Sources of Truth:

    • AC/CCs: GRID and DID both display on the Donor Tracking Sheet. If you need to validate one or both identifiers, use the Donor Tracking Sheet as your source document for traceability and validation.
    • DCs: STAR Link Web
    • TCs: MatchSource®


    • NMDP/Be The Match product labels are utilizing GRID as the only identifier on the product. For a period of time, some of the accompanying documentation/tags may still include a field for both GRID and DID after the Dec. 15 transition.
      • NMDP/Be The Match system-generated blood sample labels display only GRID. Sample labels include verification/CT, IDM and donor workup/collection samples.
      • Until Jan. 31, 2021, hand-written blood sample label templates may display both GRID and DID.
      • Until Jan. 31, 2021, accompanying documentation for product and sample labels may display both GRID and DID.

    Completing Forms:

    • For centers completing NMDP/Be The Match documentation, it is preferred that non-GRID ID fields contain “N/A” (Not Applicable) as a standard. No fields should be left blank. Incoming documentation that is populated with GRID and DID will be accepted until forms are updated to remove the DID field.
    • For those registries that are not implementing GRID, you will also see a Registry Donor ID field. This field is only applicable if a GRID does not exist; when completing forms for these registries, the GRID field should be completed as “N/A” (Not Applicable).
    • Due to the size and scope of decommissioning DID and the impact of COVID, NMDP®/Be The Match® has been granted an extension to update our documents to meet this mandate and will complete all updates no later than June 30, 2021.


    Please check our GRID FAQ document above. You can use Ctrl+F to search for a keyword in the document.

    If you still have questions, please reach out to your Be The Match contact.