OCN Lookup: Operating Company Numbers

What is an OCN?

An Operating Company Number (OCN) is a 4-character identifier assigned to each telecommunications carrier by NECA (National Exchange Carrier Association). It uniquely identifies the company that provides service for a phone number.

While carrier names can vary in formatting ("Verizon Wireless", "Verizon", "VZW"), the OCN is consistent and reliable for programmatic decisions.

OCN Format

OCNs follow a specific pattern:

• 4 characters — Always exactly 4 characters
• Alphanumeric — Letters and/or numbers
• Unique per carrier — Each OCN maps to one company

Example OCNs

Why Use OCN?

Reliable Carrier Identification

Carrier names vary in how they're reported:

• "Verizon Wireless" vs "Verizon" vs "Cellco Partnership"
• "AT&T Mobility" vs "Cingular" vs "AT&T Wireless"

The OCN is always consistent, making it ideal for:

• Routing logic and switch statements
• Billing and rate calculations
• Analytics and reporting
• Carrier-specific handling

Using OCN in API Responses

curl -X POST https://api-service.verirouteintel.io/api/v1/lrn \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"phone_number": "15551234567"}'

# Response
{
  "data": {
    "phone_number": "15551234567",
    "lrn": "5551230000",
    "carrier": "Verizon Wireless"
  },
  "success": true
}

Implementation Example

# Route based on OCN for reliable carrier matching
CARRIER_ROUTES = {
    "6006": "verizon_direct",   # Verizon Wireless
    "6529": "tmobile_direct",   # T-Mobile
    "6664": "att_direct",       # AT&T Mobility
}

VoIP_OCNs = {"9208", "7850", "8825", "6718"}  # Bandwidth, Twilio, etc.

def get_route(phone_lookup):
    ocn = phone_lookup['lrn']['ocn']

    # Check for direct carrier routes
    if ocn in CARRIER_ROUTES:
        return CARRIER_ROUTES[ocn]

    # Check for VoIP (may need special handling)
    if ocn in VOIP_OCNS:
        return "voip_route"

    # Default route
    return "general_route"

OCN vs. SPID

You may also encounter SPID (Service Provider ID):

In practice, OCN and SPID often refer to the same carrier. VeriRoute Intel returns the OCN for consistent carrier identification.

Maintaining OCN Lists

If you're building routing logic based on OCN, consider:

1. Start with major carriers — Top 10 OCNs cover most traffic
2. Group by carrier type — Wireless, landline, VoIP
3. Update periodically — New carriers emerge, mergers happen
4. Have a default route — Handle unknown OCNs gracefully