Nature of Operations	12 Months Ended
Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	Nature of Operations Anterix Inc. (the “Company”) is the nation’s largest holder of licensed 900 MHz spectrum (896-901/935-940 MHz) with coverage spanning the contiguous United States, Hawaii, Alaska, and Puerto Rico. The Company’s mission is to transform critical infrastructure connectivity, commercialize its spectrum assets and deliver advanced intelligent infrastructure solutions, including private broadband networks, tower access, and turnkey connectivity management, to utility and critical infrastructure enterprises seeking to enhance operational efficiency, strengthen grid resilience, and accelerate digital transformation. The Company was originally incorporated in California in 1997 and reincorporated in Delaware in 2014. In November 2015, the Company changed its name from Pacific DataVision, Inc. to pdvWireless, Inc. In August 2019, the Company changed its name from pdvWireless, Inc. to Anterix Inc. The Company maintains offices in Woodland Park, New Jersey, McLean, Virginia and Abilene, Texas. Business Developments During fiscal 2026, the Company evolved its business strategy. Building on its foundational 900 MHz spectrum position, the Company transitioned from a model focused predominantly on long-term spectrum leasing to a broader operating model. In the ordinary course of business, the Company now secures and expands its spectrum position, clears and retunes spectrum, monetizes spectrum through both sales and long-term leases, and develops a growing portfolio of products and services offerings around its spectrum that are designed to generate recurring revenue. Together, these activities form the foundation of how the Company generates revenue today and how it expects to generate revenue over time. The Company’s new brand and visual identity, introduced during the fourth quarter, reflects this evolution. On March 30, 2026, the Company entered into a spectrum license sale agreement with NorthWestern Energy (“NWE”) to provide 900 MHz Broadband Spectrum in the 10 MHz broadband configuration, (the “NWE Agreement”) for a total consideration of $7.7 million. This agreement marks the Company’s first deployment of 10 MHz broadband configuration in the 900 MHz band providing the foundation NWE needs to build a secure platform for a modern grid, enabling the delivery of safe, reliable energy for the communities they serve. On March 25, 2026, the Company entered into a spectrum license sale agreement with Texas-New Mexico Power Company (“TNMP”) to provide 900 MHz Broadband Spectrum covering Brazoria County and Galveston County, Texas, (the “TNMP Agreement”) for a total consideration of $3.2 million, facilitating TNMP to deploy a mission- critical private wireless network designed to strengthen grid reliability and support essential service improvements across its territory. On February 18, 2026, the Federal Communications Commission (the “FCC”) adopted the 2026 Report and Order to expand 900 MHz band to 10 MHz. On January 30, 2026, the Company entered into a spectrum license sale agreement with CPS Energy (“CPS”) to provide 900 MHz broadband license covering Bexar County, Texas, (the “CPS Agreement”) for a total payment of $13.0 million, facilitating CPS to deploy a utility private wireless broadband network that will strengthen its grid operations, enhance reliability, and accelerate innovation at scale. In November 2025, the Company and Crown Castle, one of the nation’s largest tower companies, announced a new turnkey tower service, TowerXTM, that helps utilities accelerate buildout timelines by providing access to pre-negotiated tower sites, centralized data and expert support. Additionally, the Company also relaunched CatalyX®, a turnkey SIM provisioning, connectivity management and roaming solution that helps utilities efficiently and securely activate and manage devices across public and private networks.

Anterix Inc. (the “Company”) is the nation’s largest holder of licensed 900 MHz spectrum (896-901/935-940 MHz) with coverage spanning the contiguous United States, Hawaii, Alaska, and Puerto Rico. The Company’s mission is to transform critical infrastructure connectivity, commercialize its spectrum assets and deliver advanced intelligent infrastructure solutions, including private broadband networks, tower access, and turnkey connectivity management, to utility and critical infrastructure enterprises seeking to enhance operational efficiency, strengthen grid resilience, and accelerate digital transformation.

The Company was originally incorporated in California in 1997 and reincorporated in Delaware in 2014. In November 2015, the Company changed its name from Pacific DataVision, Inc. to pdvWireless, Inc. In August 2019, the Company changed its name from pdvWireless, Inc. to Anterix Inc. The Company maintains offices in Woodland Park, New Jersey, McLean, Virginia and Abilene, Texas.

During fiscal 2026, the Company evolved its business strategy. Building on its foundational 900 MHz spectrum position, the Company transitioned from a model focused predominantly on long-term spectrum leasing to a broader operating model. In the ordinary course of business, the Company now secures and expands its spectrum position, clears and retunes spectrum, monetizes spectrum through both sales and long-term leases, and develops a growing portfolio of products and services offerings around its spectrum that are designed to generate recurring revenue. Together, these activities form the foundation of how the Company generates revenue today and how it expects to generate revenue over time. The Company’s new brand and visual identity, introduced during the fourth quarter, reflects this evolution.

On March 30, 2026, the Company entered into a spectrum license sale agreement with NorthWestern Energy (“NWE”) to provide 900 MHz Broadband Spectrum in the 10 MHz broadband configuration, (the “NWE Agreement”) for a total consideration of $7.7 million. This agreement marks the Company’s first deployment of 10 MHz broadband configuration in the 900 MHz band providing the foundation NWE needs to build a secure platform for a modern grid, enabling the delivery of safe, reliable energy for the communities they serve.

On March 25, 2026, the Company entered into a spectrum license sale agreement with Texas-New Mexico Power Company (“TNMP”) to provide 900 MHz Broadband Spectrum covering Brazoria County and Galveston County, Texas, (the “TNMP Agreement”) for a total consideration of $3.2 million, facilitating TNMP to deploy a mission- critical private wireless network designed to strengthen grid reliability and support essential service improvements across its territory.

On January 30, 2026, the Company entered into a spectrum license sale agreement with CPS Energy (“CPS”) to provide 900 MHz broadband license covering Bexar County, Texas, (the “CPS Agreement”) for a total payment of $13.0 million, facilitating CPS to deploy a utility private wireless broadband network that will strengthen its grid operations, enhance reliability, and accelerate innovation at scale.

In November 2025, the Company and Crown Castle, one of the nation’s largest tower companies, announced a new turnkey tower service, TowerXTM, that helps utilities accelerate buildout timelines by providing access to pre-negotiated tower sites, centralized data and expert support.

Additionally, the Company also relaunched CatalyX®, a turnkey SIM provisioning, connectivity management and roaming solution that helps utilities efficiently and securely activate and manage devices across public and private networks.