Exhibit 4.18

   

  EXECUTION VERSION

   

   EIGHTEENTH SUPPLEMENTAL INDENTURE

   

  EIGHTEENTH SUPPLEMENTAL INDENTURE (this “Eighteenth Supplemental
        Indenture”), dated as of March 30, 2021, among T-Mobile USA, Inc. (the “Issuer”), the entities listed on Schedule I hereto (the “New Guarantors”), the existing guarantors signatory hereto (the “Existing
        Guarantors”) and Deutsche Bank Trust Company Americas, as trustee (the “Trustee”) under the Indenture referred to below.

   

  WITNESSETH:

   

  WHEREAS, the Issuer is party to the Indenture, dated as of April 9, 2020
      (the “Base Indenture”) among the Issuer, T-Mobile US, Inc., a Delaware corporation, as a guarantor, and the Trustee, as amended and supplemented with respect to the Issuer’s (a) 3.500% Senior Secured Notes due 2025 by the First Supplemental
      Indenture dated as of April 9, 2020, (b) 3.750% Senior Secured Notes due 2027 by the Second Supplemental Indenture dated as of April 9, 2020, (c) 3.875% Senior Secured Notes due 2030 by the Third Supplemental Indenture dated as of April 9, 2020, (d)
      4.375% Senior Secured Notes due 2040 by the Fourth Supplemental Indenture dated as of April 9, 2020, (e) 4.500% Senior Secured Notes due 2050 by the Fifth Supplemental Indenture dated as of April 9, 2020, (f) 1.500% Senior Secured Notes due 2026 by
      the Seventh Supplemental Indenture dated as of June 24, 2020, (g) 2.050% Senior Secured Notes due 2028 by the Eighth Supplemental Indenture dated as of June 24, 2020 and the Tenth Supplemental Indenture dated as of October 6, 2020, (h) 2.550% Senior
      Secured Notes due 2031 by the Ninth Supplemental Indenture dated as of June 24, 2020 and the Eleventh Supplemental Indenture dated as of October 6, 2020, (i) 3.000% Senior Secured Notes due 2041 by the Twelfth Supplemental Indenture dated as of
      October 6, 2020 and the Fifteenth Supplemental Indenture dated as of October 28, 2020, (j) 3.300% Senior Secured Notes due 2051 by the Thirteenth Supplemental Indenture dated as of October 6, 2020 and the Sixteenth Supplemental Indenture dated as of
      October 28, 2020, (k) 2.250% Senior Secured Notes due 2031 by the Fourteenth Supplemental Indenture dated as of October 28, 2020, and (l) 3.600% Senior Secured Notes due 2060 by the Seventeenth Supplemental Indenture dated as of October 28, 2020, and
      as amended and supplemented by the Sixth Supplemental Indenture dated as of May 7, 2020 (the Base Indenture as so amended and supplemented, the “Indenture”);

   

  WHEREAS, Section 4.09 of the Indenture provides that under certain
      circumstances the Issuer is required to cause the New Guarantors to execute and deliver to the Trustee a supplemental indenture pursuant to which each of the New Guarantors shall become a Guarantor of the applicable Notes on the terms and conditions
      set forth herein; and

   

  WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee, the
      Issuer, the Existing Guarantors and the New Guarantors are authorized to execute and deliver this Eighteenth Supplemental Indenture.

   

  NOW THEREFORE, in consideration of the foregoing and for other good and
      valuable consideration, the receipt of which is hereby acknowledged, the Issuer, the New Guarantors, the Existing Guarantors and the Trustee mutually covenant and agree for the benefit of the Holders of the applicable Notes as follows:

   

  1.       Defined Terms. As used in this Eighteenth Supplemental
      Indenture, capitalized terms used but not defined herein shall have the meaning set forth in the Indenture. The words “herein,” “hereof” and “hereby” and other words of similar import used in this Eighteenth Supplemental Indenture refer to this
      Eighteenth Supplemental Indenture as a whole and not to any particular section hereof.

   

  

  
     

    
      
 

  

   

  2.       Agreement to Guarantee. The New
      Guarantors hereby agree, jointly and severally, to unconditionally guarantee, and the Existing Guarantors hereby affirm their joint and several unconditional guarantee of, the Issuer’s obligations under the Notes and the Indenture on the terms and
      subject to the conditions set forth in the Indenture including but not limited to ARTICLE X thereof.

   

  3.       Notices. All notices or other
      communications to the Issuer and the New Guarantors shall be given as provided in Section 12.02 of the Indenture.

   

  4.       Ratification of Indenture; Supplemental
        Indentures Part of Indenture. Except as expressly contemplated hereby, the Indenture is in all respects ratified and confirmed and all the terms, conditions and provisions thereof shall remain in full force and effect.

   

  5.       Governing Law. THIS EIGHTEENTH
      SUPPLEMENTAL INDENTURE WILL BE GOVERNED BY THE LAWS OF THE STATE OF NEW YORK.

   

  6       The Trustee. The Trustee shall not be
      responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Eighteenth Supplemental Indenture or for or in respect of the recitals contained herein, all of which recitals are made solely by the New Guarantors and the
      Issuer.

   

  7.       Counterpart Originals. This Eighteenth
      Supplemental Indenture may be executed in any number of counterparts and by the parties hereto in separate counterparts, each of which when so executed will be deemed to be an original and all of which taken together will constitute one and the same
      agreement. The exchange of copies of this Eighteenth Supplemental Indenture and of signature pages by facsimile or electronic transmission shall constitute effective execution and delivery of this Eighteenth Supplemental Indenture as to the parties
      hereto and may be used in lieu of the original Eighteenth Supplemental Indenture for all purposes. Signatures of the parties hereto transmitted by facsimile or electronic transmission shall be deemed to be their original signatures for all purposes.
      The parties may sign any number of copies of this Eighteenth Supplemental Indenture. Each signed copy will be an original, but all of them together represent the same agreement.

   

  8.       Headings, etc. The headings of the
      Articles and Sections of this Eighteenth Supplemental Indenture have been inserted for convenience of reference only, are not to be considered a part of this Eighteenth Supplemental Indenture and will in no way modify or restrict any of the terms or
      provisions hereof.

   

  [Signatures on following page]

   

  
     

    
      
 

  

   

  IN WITNESS WHEREOF, the parties hereto have caused this Eighteenth Supplemental
      Indenture to be duly executed, as of the date first above written.

   

  	 	T-MOBILE INNOVATIONS LLC
	 	 
	 	By:	/s/ Johannes Thorsteinsson
	 	 	Name:	Johannes Thorsteinsson
	 	 	Title:	Senior Vice President, Treasury & Treasurer


   

  

  [Eighteenth Supplemental Indenture]

   

  

  
     

    
      
 

  

   

  	 	TVN VENTURES LLC
	 	 
	 	By:	/s/ Johannes Thorsteinsson
	 	 	Name:	Johannes Thorsteinsson
	 	 	Title:	Senior Vice President, Treasury & Treasurer


   

  [Eighteenth Supplemental Indenture]

   

  
     

    
      
 

  

   

  	 	T-MOBILE USA, INC.
	 	 
	 	By:	/s/ Johannes Thorsteinsson
	 	 	Name:	Johannes Thorsteinsson
	 	 	Title:	Senior Vice President, Treasury & Treasurer


   

  	 	T-MOBILE US, INC.
	 	 
	 	By:	/s/ Johannes Thorsteinsson
	 	 	Name:	Johannes Thorsteinsson
	 	 	Title:	Senior Vice President, Treasury & Treasurer


   

  [Eighteenth Supplemental Indenture]

   

  
     

    
      
 

  

   

  	 	ALDA WIRELESS HOLDINGS, LLC
	 	AMERICAN TELECASTING DEVELOPMENT, LLC
	 	AMERICAN TELECASTING OF ANCHORAGE, LLC
	 	AMERICAN TELECASTING OF COLUMBUS, LLC
	 	AMERICAN TELECASTING OF DENVER, LLC
	 	AMERICAN TELECASTING OF FORT MYERS, LLC
	 	AMERICAN TELECASTING OF FT. COLLINS, LLC
	 	AMERICAN TELECASTING OF GREEN BAY, LLC
	 	AMERICAN TELECASTING OF LANSING, LLC
	 	AMERICAN TELECASTING OF LINCOLN, LLC
	 	AMERICAN TELECASTING OF LITTLE ROCK, LLC
	 	AMERICAN TELECASTING OF LOUISVILLE, LLC
	 	AMERICAN TELECASTING OF MEDFORD, LLC
	 	AMERICAN TELECASTING OF MICHIANA, LLC
	 	AMERICAN TELECASTING OF MONTEREY, LLC
	 	AMERICAN TELECASTING OF REDDING, LLC
	 	AMERICAN TELECASTING OF SANTA BARBARA, LLC
	 	AMERICAN TELECASTING OF SEATTLE, LLC
	 	AMERICAN TELECASTING OF SHERIDAN, LLC
	 	AMERICAN TELECASTING OF YUBA CITY, LLC
	 	APC REALTY AND EQUIPMENT COMPANY, LLC
	 	ASSURANCE WIRELESS OF SOUTH CAROLINA, LLC
	 	ASSURANCE WIRELESS USA, L.P.
	 	ATI SUB, LLC
	 	BROADCAST CABLE, LLC
	 	CLEAR WIRELESS LLC
	 	CLEARWIRE COMMUNICATIONS LLC
	 	CLEARWIRE HAWAII PARTNERS SPECTRUM, LLC
	 	CLEARWIRE IP HOLDINGS LLC
	 	CLEARWIRE LEGACY LLC
	 	CLEARWIRE SPECTRUM HOLDINGS II LLC
	 	CLEARWIRE SPECTRUM HOLDINGS III LLC
	 	CLEARWIRE SPECTRUM HOLDINGS LLC
	 	CLEARWIRE XOHM LLC
	 	FIXED WIRELESS HOLDINGS, LLC
	 	FRESNO MMDS ASSOCIATES, LLC
	 	IBSV LLC
	 	KENNEWICK LICENSING, LLC
	 	L3TV CHICAGOLAND CABLE SYSTEM, LLC
	 	L3TV COLORADO CABLE SYSTEM, LLC, each as a Guarantor


   

  	 	By:	/s/ Johannes Thorsteinsson	 
	 	Name:     Johannes Thorsteinsson	 
	 	Title:       Senior Vice President, Treasury & Treasurer	 


   

  [Eighteenth Supplemental Indenture]

   

  
     

    
      
 

  

   

  	 	L3TV DALLAS CABLE SYSTEM, LLC
	 	L3TV DC CABLE SYSTEM, LLC
	 	L3TV DETROIT CABLE SYSTEM, LLC
	 	L3TV LOS ANGELES CABLE SYSTEM, LLC
	 	L3TV MINNEAPOLIS CABLE SYSTEM, LLC
	 	L3TV NEW YORK CABLE SYSTEM, LLC
	 	L3TV PHILADELPHIA CABLE SYSTEM, LLC
	 	L3TV SAN FRANCISCO CABLE SYSTEM, LLC
	 	L3TV SEATTLE CABLE SYSTEM, LLC
	 	LAYER3 TV, LLC
	 	METROPCS CALIFORNIA, LLC
	 	METROPCS FLORIDA, LLC
	 	METROPCS GEORGIA, LLC
	 	METROPCS MASSACHUSETTS, LLC
	 	METROPCS MICHIGAN, LLC
	 	METROPCS NETWORKS CALIFORNIA, LLC
	 	METROPCS NETWORKS FLORIDA, LLC
	 	METROPCS NEVADA, LLC
	 	METROPCS NEW YORK, LLC
	 	METROPCS PENNSYLVANIA, LLC
	 	METROPCS TEXAS, LLC
	 	MINORCO, LLC
	 	NEXTEL COMMUNICATIONS OF THE MID-ATLANTIC, INC.
	 	NEXTEL OF NEW YORK, INC.
	 	NEXTEL RETAIL STORES, LLC
	 	NEXTEL SOUTH CORP.
	 	NEXTEL SYSTEMS, LLC
	 	NEXTEL WEST CORP.
	 	NSAC, LLC
	 	PCTV GOLD II, LLC
	 	PCTV SUB, LLC
	 	PEOPLE’S CHOICE TV OF HOUSTON, LLC
	 	PEOPLE’S CHOICE TV OF ST. LOUIS, LLC
	 	PRWIRELESS PR, LLC
	 	PUSHSPRING, INC.
	 	SFE 1, LLC
	 	SIHI NEW ZEALAND HOLDCO, INC.
	 	SPEEDCHOICE OF DETROIT, LLC
	 	SPEEDCHOICE OF PHOENIX, LLC, each as a Guarantor


   

  	 	By:	/s/ Johannes Thorsteinsson	 
	 	Name:     Johannes Thorsteinsson	 
	 	Title:      Senior Vice President, Treasury & Treasurer	 


   

  [Eighteenth Supplemental Indenture]

   

  
     

    
      
 

  

   

  	 	SPRINT (BAY AREA), LLC
	 	SPRINT CAPITAL CORPORATION
	 	SPRINT COMMUNICATIONS COMPANY L.P.
	 	SPRINT COMMUNICATIONS COMPANY OF NEW HAMPSHIRE, INC.
	 	SPRINT COMMUNICATIONS COMPANY OF VIRGINIA, INC.
	 	SPRINT COMMUNICATIONS, INC.
	 	SPRINT CORPORATION

          
	 	SPRINT EBUSINESS, INC.
	 	SPRINT ENTERPRISE NETWORK SERVICES, INC.
	 	SPRINT EWIRELESS, INC.
	 	SPRINT INTERNATIONAL COMMUNICATIONS CORPORATION
	 	SPRINT INTERNATIONAL HOLDING, INC.
	 	SPRINT INTERNATIONAL INCORPORATED
	 	SPRINT INTERNATIONAL NETWORK COMPANY LLC
	 	SPRINT PCS ASSETS, L.L.C.
	 	SPRINT SOLUTIONS, INC.
	 	SPRINT SPECTRUM HOLDING COMPANY, LLC
	 	SPRINT SPECTRUM REALTY COMPANY, LLC
	 	SPRINT/UNITED MANAGEMENT COMPANY
	 	TDI ACQUISITION SUB, LLC
	 	THEORY MOBILE, INC.
	 	T-MOBILE LICENSE LLC
	 	T-MOBILE NORTHEAST LLC
	 	T-MOBILE PCS HOLDINGS LLC
	 	T-MOBILE PUERTO RICO HOLDINGS LLC
	 	T-MOBILE PUERTO RICO LLC
	 	T-MOBILE RESOURCES LLC
	 	T-MOBILE SOUTH LLC
	 	T-MOBILE WEST LLC
	 	TMUS INTERNATIONAL LLC
	 	TRANSWORLD TELECOM II, LLC
	 	USST OF TEXAS, INC.
	 	UTELCOM LLC
	 	VMU GP, LLC
	 	WBS OF AMERICA, LLC, each as a Guarantor


   

  	 	By:	/s/ Johannes Thorsteinsson	 
	 	Name:     Johannes Thorsteinsson	 
	 	Title:       Senior Vice President, Treasury & Treasurer	 


   

  [Eighteenth Supplemental Indenture]

   

  
     

    
      
 

  

   

  	 	WBS OF SACRAMENTO, LLC
	 	WBSY LICENSING, LLC
	 	WCOF, LLC
	 	WIRELESS BROADBAND SERVICES OF AMERICA, L.L.C.
	 	WIRELINE LEASING CO., INC., each as a Guarantor


   

  	 	By:	/s/ Johannes Thorsteinsson	 
	 	Name:     Johannes Thorsteinsson	 
	 	Title:      Senior Vice President, Treasury & Treasurer	 


   

  	 	SPRINTCOM, INC.
	 	SPRINT SPECTRUM L.P.
	 	T-MOBILE FINANCIAL LLC
	 	T-MOBILE LEASING LLC, each as a Guarantor


   

  	 	By:	/s/ Johannes Thorsteinsson	 
	 	Name:     Johannes Thorsteinsson	 
	 	Title:      Assistant Treasurer	 


   

  	 	T-MOBILE CENTRAL LLC, as a Guarantor	 
	 	 	 	 
	 	By:	/s/ Johannes Thorsteinsson	 
	 	Name:    Johannes Thorsteinsson	 
	 	Title:      Vice President	 


   

  [Eighteenth Supplemental Indenture]

   

  
     

    
      
 

  

   

  	 	DEUTSCHE BANK TRUST COMPANY AMERICAS, as Trustee
	 	 	 	 
	 	By:	/s/ Jeffrey Schoenfeld

        
	 	 	Name:	Jeffrey Schoenfeld
	 	 	Title:	Vice President

        
	 	 	 	 
	 	By:	/s/ Chris Niesz

        
	 	 	Name:	Chris Niesz

        
	 	 	Title:	Vice President

        


   

  [Eighteenth Supplemental Indenture]

   

  

  
     

    
      
 

  

  
   

  Schedule I

   

  	Entity	Jurisdiction of

            Organization
	 T-MOBILE INNOVATIONS LLC	Delaware
	 TVN VENTURES LLC	Delaware