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npa-nxxState/ProvinceCompanyFRNRMDOCNRate CenterCLLIAssign DateMisc
406-617MTNEW CINGULAR WIRELESS PCS, LLC (AT&T)0003291192RMD00369096010BILLINGSBLNGMTMAMMD12/23/2024Prefix Type: WIRELESS
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
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406-617 is split into 1,000-number blocks - detail below
406-617-0XXXMTNUSO, LLC0028048908RMD0001599732JBILLINGSBLNGMTMAX6X12/31/2024Prefix Type: IPES
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
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406-617-1XXXMTNUSO, LLC0028048908RMD0001599732JBILLINGSBLNGMTMAX6X12/31/2024Prefix Type: IPES
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
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406-617-2XXXMTT-MOBILE USA, INC. (T-Mobile US, Inc)0017078262RMD00190516529BILLINGSBLNGMTVR1MD03/07/2025Prefix Type: PCS
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
🔧 Explore Switch(CLLI: BLNGMTVR1MD))
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406-617-3XXXMTT-MOBILE USA, INC. (T-Mobile US, Inc)0017078262RMD00190516529BILLINGSBLNGMTVR1MD07/28/2025Prefix Type: PCS
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
🔧 Explore Switch(CLLI: BLNGMTVR1MD))
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406-617-4XXXMTT-MOBILE USA, INC. (T-Mobile US, Inc)0017078262RMD00190516529BILLINGSBLNGMTVR1MD06/26/2025Prefix Type: PCS
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
🔧 Explore Switch(CLLI: BLNGMTVR1MD))
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406-617-5XXXMTT-MOBILE USA, INC. (T-Mobile US, Inc)0017078262RMD00190516529BILLINGSBLNGMTVR1MD06/26/2025Prefix Type: PCS
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
🔧 Explore Switch(CLLI: BLNGMTVR1MD))
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406-617-6XXXMTT-MOBILE USA, INC. (T-Mobile US, Inc)0017078262RMD00190516529BILLINGSBLNGMTVR1MD05/15/2025Prefix Type: PCS
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
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406-617-7XXXMTTELNYX LLC (TELNYX LLC)0018998724RMD0001645073HBILLINGSBLNGMT933MD01/03/2025Prefix Type: IPES
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
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406-617-8XXXMTNEW CINGULAR WIRELESS PCS, LLC (AT&T)0003291192RMD00369096010BILLINGSBLNGMTMAMMD12/23/2024Prefix Type: WIRELESS
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
🔧 Explore Switch(CLLI: BLNGMTMAMMD))
🕘 Prefix History
🔎 Explore Carrier Information
📡 Find related FCC/ISED radio licenses
406-617-9XXXMTT-MOBILE USA, INC. (T-Mobile US, Inc)0017078262RMD00190516529BILLINGSBLNGMTVR1MD01/07/2026Prefix Type: PCS
Switch Name: N/A
Switch Type: N/A
LATA: Billings MT (650)
Tandem: N/A
🔧 Explore Switch(CLLI: BLNGMTVR1MD))
🕘 Prefix History
🔎 Explore Carrier Information
📡 Find related FCC/ISED radio licenses
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