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United States (us)

us

  • System: http://hl7.org/fhir/sid/us-ssn
  • Format: NNN-NN-NNNN (AAA-GG-SSSS)
  • Generation rules: Area codes are drawn from the 900–999 range, which the Social Security Administration has never assigned to real people. The IRS reserved range 987-65-43XX is excluded. Group and serial numbers are randomised within valid ranges (non-zero).
  • Algorithm: Format and range validation only (no check digit).
  • System: http://hospital.example.org/fhir/mrn
  • Format: Two uppercase letters followed by six digits (e.g. AB123456)
  • Algorithm: Format validation only.

Note: This MRN system URI is a placeholder. Real deployments use facility-specific NamingSystem URIs.

  • System: http://hl7.org/fhir/sid/us-npi
  • Format: 10 digits
  • Algorithm: Luhn — the NPI check digit is computed against the string 80840 prepended to the nine-digit base, per the CMS NPI standard.

NPIs are also used for organisations, using the same system URI and algorithm.

Standard US format: street number + street name, city, state abbreviation, five-digit ZIP code. Country code US.

Common US given and family names.