ASN AS19721 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS19721?

AS19721 is listed under Magellan Health Services.

What do peers, upstreams, and downstreams mean in ASN data?

Peers are lateral network interconnections, upstreams are transit providers, and downstreams are customer networks receiving connectivity.

What are routes and IP ranges for an ASN?

Routes and IP ranges are the network prefixes announced by the ASN on the internet and show the address space it originates.

Why is WHOIS data shown for an ASN?

WHOIS data provides registration and contact context for ASN ownership, administration, and operational reference.

How can I access the full ASN tables?

The page shows a preview of large ASN datasets. Use the page controls to load more rows, and upgrade to a paid plan for complete access.

AS19721 Magellan Health Services

ASN Lookup Tool

Magellan Health Services magellanhealth.com

US 14 Routes

AS Data

AS19721

AS19721 – Magellan Health Services

AS Number	19721
AS Name	MHN
Organization	Magellan Health Services (mhs-54)
Country	US
Website	magellanhealth.com
Number of IPv4 Routes	14
Number of IPv6 Routes	0
ASN type	BUSINESS
Registry	ARIN
Date Allocated	2001-02-07

ASN Intelligence API for production workflows

Use ASN data for AS19721 in automation: routing intelligence, peering analysis, ownership checks, and network observability.

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IP Ranges

Route	Origin	Origin Name	ISP	# IPs
204.193.86.0/23	AS19721	Magellan Health Services	MagellanBehavioralHealth	512
204.193.84.0/24	AS19721	Magellan Health Services	MagellanBehavioralHealth	256
204.193.74.0/24	AS19721	Magellan Health Services	MagellanBehavioralHealth	256
204.193.71.0/24	AS19721	Magellan Health Services	MagellanBehavioralHealth	256
204.193.80.0/24	AS19721	Magellan Health Services	MagellanBehavioralHealth	256
204.193.93.0/24	AS19721	Magellan Health Services	MagellanBehavioralHealth	256
204.193.80.0/20	AS19721	Magellan Health Services	MagellanBehavioralHealth	4096
204.193.75.0/24	AS19721	Magellan Health Services	MagellanBehavioralHealth	256
204.193.64.0/20	AS19721	Magellan Health Services	MagellanBehavioralHealth	4096
204.193.72.0/24	AS19721	Magellan Health Services	MagellanBehavioralHealth	256
204.193.88.0/24	AS19721	Magellan Health Services	MagellanBehavioralHealth	256
204.193.85.0/24	AS19721	Magellan Health Services	MagellanBehavioralHealth	256
204.193.84.0/22	AS19721	Magellan Health Services	MagellanBehavioralHealth	1024
204.193.64.0/19	AS19721	Magellan Health Services	MagellanBehavioralHealth	8192

Raw Whois Response

#
# ARIN WHOIS data and services are subject to the Terms of Use
# available at: https://www.arin.net/resources/registry/whois/tou/
#
# If you see inaccuracies in the results, please report at
# https://www.arin.net/resources/registry/whois/inaccuracy_reporting/
#
# Copyright 1997-2026, American Registry for Internet Numbers, Ltd.
#


ASNumber:       19721
ASName:         MHN
ASHandle:       AS19721
RegDate:        2001-02-07
Updated:        2012-03-20
Ref:            https://rdap.arin.net/registry/autnum/19721


OrgName:        Magellan Health Services
OrgId:          MHS-54
Address:        13736 Riverport Dr.
City:           Maryland Heights
StateProv:      MO
PostalCode:     63043
Country:        US
RegDate:        2001-02-07
Updated:        2026-06-05
Ref:            https://rdap.arin.net/registry/entity/MHS-54


OrgNOCHandle: STLNE-ARIN
OrgNOCName:   stlnetengineering
OrgNOCPhone:  +1-314-387-4000 
OrgNOCEmail:  NetworkInfrastructure@magellanhealth.com
OrgNOCRef:    https://rdap.arin.net/registry/entity/STLNE-ARIN

OrgTechHandle: WEBBA33-ARIN
OrgTechName:   Webb, Arron 
OrgTechPhone:  +1-832-622-0113 
OrgTechEmail:  webba3@magellanhealth.com
OrgTechRef:    https://rdap.arin.net/registry/entity/WEBBA33-ARIN

OrgRoutingHandle: WEBBA33-ARIN
OrgRoutingName:   Webb, Arron 
OrgRoutingPhone:  +1-832-622-0113 
OrgRoutingEmail:  webba3@magellanhealth.com
OrgRoutingRef:    https://rdap.arin.net/registry/entity/WEBBA33-ARIN

OrgDNSHandle: WEBBA33-ARIN
OrgDNSName:   Webb, Arron 
OrgDNSPhone:  +1-832-622-0113 
OrgDNSEmail:  webba3@magellanhealth.com
OrgDNSRef:    https://rdap.arin.net/registry/entity/WEBBA33-ARIN

OrgAbuseHandle: WEBBA33-ARIN
OrgAbuseName:   Webb, Arron 
OrgAbusePhone:  +1-832-622-0113 
OrgAbuseEmail:  webba3@magellanhealth.com
OrgAbuseRef:    https://rdap.arin.net/registry/entity/WEBBA33-ARIN

OrgNOCHandle: WEBBA33-ARIN
OrgNOCName:   Webb, Arron 
OrgNOCPhone:  +1-832-622-0113 
OrgNOCEmail:  webba3@magellanhealth.com
OrgNOCRef:    https://rdap.arin.net/registry/entity/WEBBA33-ARIN

OrgDNSHandle: HEAPB-ARIN
OrgDNSName:   Heap, Brandon 
OrgDNSPhone:  +1-801-367-9127 
OrgDNSEmail:  heapb@magellanhealth.com
OrgDNSRef:    https://rdap.arin.net/registry/entity/HEAPB-ARIN

OrgAbuseHandle: STLNE-ARIN
OrgAbuseName:   stlnetengineering
OrgAbusePhone:  +1-314-387-4000 
OrgAbuseEmail:  NetworkInfrastructure@magellanhealth.com
OrgAbuseRef:    https://rdap.arin.net/registry/entity/STLNE-ARIN

OrgTechHandle: HEAPB-ARIN
OrgTechName:   Heap, Brandon 
OrgTechPhone:  +1-801-367-9127 
OrgTechEmail:  heapb@magellanhealth.com
OrgTechRef:    https://rdap.arin.net/registry/entity/HEAPB-ARIN

OrgRoutingHandle: HEAPB-ARIN
OrgRoutingName:   Heap, Brandon 
OrgRoutingPhone:  +1-801-367-9127 
OrgRoutingEmail:  heapb@magellanhealth.com
OrgRoutingRef:    https://rdap.arin.net/registry/entity/HEAPB-ARIN

OrgNOCHandle: HEAPB-ARIN
OrgNOCName:   Heap, Brandon 
OrgNOCPhone:  +1-801-367-9127 
OrgNOCEmail:  heapb@magellanhealth.com
OrgNOCRef:    https://rdap.arin.net/registry/entity/HEAPB-ARIN

OrgAbuseHandle: HEAPB-ARIN
OrgAbuseName:   Heap, Brandon 
OrgAbusePhone:  +1-801-367-9127 
OrgAbuseEmail:  heapb@magellanhealth.com
OrgAbuseRef:    https://rdap.arin.net/registry/entity/HEAPB-ARIN

OrgTechHandle: STLNE-ARIN
OrgTechName:   stlnetengineering
OrgTechPhone:  +1-314-387-4000 
OrgTechEmail:  NetworkInfrastructure@magellanhealth.com
OrgTechRef:    https://rdap.arin.net/registry/entity/STLNE-ARIN

RTechHandle: DB1528-ARIN
RTechName:   Brack, David 
RTechPhone:  +1-314-387-4055 
RTechEmail:  dabrack@magellanhealth.com
RTechRef:    https://rdap.arin.net/registry/entity/DB1528-ARIN


#
# ARIN WHOIS data and services are subject to the Terms of Use
# available at: https://www.arin.net/resources/registry/whois/tou/
#
# If you see inaccuracies in the results, please report at
# https://www.arin.net/resources/registry/whois/inaccuracy_reporting/
#
# Copyright 1997-2026, American Registry for Internet Numbers, Ltd.
#

Parsed Whois Response

{
  "status" : true,
  "whois_server" : "whois.arin.net",
  "aut_nums" : [ {
    "aut_num" : "19721",
    "as_handle" : "AS19721",
    "as_name" : "MHN",
    "admin_contacts" : [ "WEBBA33-ARIN", "HEAPB-ARIN" ],
    "tech_contacts" : [ "WEBBA33-ARIN", "WEBBA33-ARIN", "HEAPB-ARIN", "HEAPB-ARIN", "STLNE-ARIN", "DB1528-ARIN" ],
    "abuse_contacts" : [ "WEBBA33-ARIN", "STLNE-ARIN", "HEAPB-ARIN" ],
    "date_created" : "2001-02-07",
    "date_updated" : "2012-03-20",
    "source" : "https://rdap.arin.net/registry/autnum/19721"
  } ],
  "organization" : {
    "handle" : "MHS-54",
    "name" : "Magellan Health Services",
    "address" : [ "13736 Riverport Dr.", "Maryland Heights", "MO", "63043", "US" ],
    "street" : "Riverport Dr.",
    "city" : "Maryland Heights",
    "state" : "MO",
    "zip_code" : "63043",
    "country" : [ "US" ],
    "date_created" : "2001-02-07",
    "date_updated" : "2026-06-05",
    "source" : "https://rdap.arin.net/registry/entity/MHS-54",
    "addressCountry" : "US"
  },
  "administrative_contacts" : [ {
    "handle" : "WEBBA33-ARIN",
    "name" : "Webb, Arron",
    "email" : [ "webba3@magellanhealth.com" ],
    "phone" : [ "+1-832-622-0113" ],
    "source" : "https://rdap.arin.net/registry/entity/WEBBA33-ARIN"
  }, {
    "handle" : "HEAPB-ARIN",
    "name" : "Heap, Brandon",
    "email" : [ "heapb@magellanhealth.com" ],
    "phone" : [ "+1-801-367-9127" ],
    "source" : "https://rdap.arin.net/registry/entity/HEAPB-ARIN"
  } ],
  "technical_contacts" : [ {
    "handle" : "WEBBA33-ARIN",
    "name" : "Webb, Arron",
    "email" : [ "webba3@magellanhealth.com" ],
    "phone" : [ "+1-832-622-0113" ],
    "source" : "https://rdap.arin.net/registry/entity/WEBBA33-ARIN"
  }, {
    "handle" : "HEAPB-ARIN",
    "name" : "Heap, Brandon",
    "email" : [ "heapb@magellanhealth.com" ],
    "phone" : [ "+1-801-367-9127" ],
    "source" : "https://rdap.arin.net/registry/entity/HEAPB-ARIN"
  }, {
    "handle" : "STLNE-ARIN",
    "name" : "stlnetengineering",
    "email" : [ "NetworkInfrastructure@magellanhealth.com" ],
    "phone" : [ "+1-314-387-4000" ],
    "source" : "https://rdap.arin.net/registry/entity/STLNE-ARIN"
  }, {
    "handle" : "DB1528-ARIN",
    "name" : "Brack, David",
    "email" : [ "dabrack@magellanhealth.com" ],
    "phone" : [ "+1-314-387-4055" ],
    "source" : "https://rdap.arin.net/registry/entity/DB1528-ARIN"
  } ],
  "abuse_contacts" : [ {
    "handle" : "WEBBA33-ARIN",
    "name" : "Webb, Arron",
    "email" : [ "webba3@magellanhealth.com" ],
    "phone" : [ "+1-832-622-0113" ],
    "source" : "https://rdap.arin.net/registry/entity/WEBBA33-ARIN"
  }, {
    "handle" : "STLNE-ARIN",
    "name" : "stlnetengineering",
    "email" : [ "NetworkInfrastructure@magellanhealth.com" ],
    "phone" : [ "+1-314-387-4000" ],
    "source" : "https://rdap.arin.net/registry/entity/STLNE-ARIN"
  }, {
    "handle" : "HEAPB-ARIN",
    "name" : "Heap, Brandon",
    "email" : [ "heapb@magellanhealth.com" ],
    "phone" : [ "+1-801-367-9127" ],
    "source" : "https://rdap.arin.net/registry/entity/HEAPB-ARIN"
  } ]
}

Peers

AS Number	Description	Country
AS49915	Megaport UK Limited	GB
AS49915	Megaport (UK) Limited	GB
AS3356	Level 3 Parent, LLC	US

Upstreams

AS Number	Description	Country
AS49915	Megaport UK Limited	GB
AS3356	Level 3 Parent, LLC	US