What is GCC High?

What is GCC High?

Government Community Cloud High (GCC High) is a physically and logically isolated Microsoft 365 cloud environment built for U.S. Department of Defense (DoD) contractors, federal agencies, and defense organizations that process controlled unclassified information (CUI) or data subject to export controls. It runs exclusively in Azure Government data centers located within the United States.

Standard commercial Microsoft 365, and even the standard Government Community Cloud (GCC) environment, do not meet the security and data handling requirements for organizations that deal with International Traffic in Arms Regulations (ITAR), Defense Federal Acquisition Regulation Supplement (DFARS), or Cybersecurity Maturity Model Certification (CMMC) requirements. GCC High fills that gap by providing FedRAMP High authorization, NIST SP 800-171 compliance, and support for ITAR and DFARS 252.204-7012. Access to GCC High production environments is restricted to Microsoft personnel who are U.S. citizens and have passed enhanced background screening, including FBI fingerprint checks and seven-year criminal record reviews. Organizations must go through a Microsoft validation process to establish a GCC High environment, which typically requires a CAGE code, active government contract, or sponsorship.

GCC High vs. GCC: What's the Difference?

GCC High and standard GCC are both government-focused Microsoft 365 environments, but they serve different audiences and operate at different security levels. GCC meets FedRAMP Moderate requirements for civilian federal, state, and local agencies, while GCC High meets FedRAMP High requirements for DoD contractors and organizations handling ITAR-controlled or export-controlled data.

The most significant differences are in isolation, compliance scope, and personnel restrictions. GCC is logically separated from the commercial cloud but relies partly on shared infrastructure, while GCC High is physically and logically isolated in Azure Government. GCC does not support ITAR, DFARS 252.204-7012, or CMMC requirements. GCC High does. Support personnel for GCC can be worldwide commercial staff, but GCC High restricts all support to screened U.S. citizens. On the voice side, GCC supports Microsoft Calling Plans, Operator Connect, and Direct Routing for Teams Phone. GCC High supports Direct Routing only, because neither Calling Plans nor Operator Connect meet the data sovereignty and compliance requirements of the GCC High boundary. GCC is the right choice for non-defense government work. GCC High is required when the contract or data type references ITAR, DFARS, or CMMC.

What types of organizations are required to use GCC High?

Organizations required to use GCC High include DoD contractors holding CUI, companies subject to ITAR or Export Administration Regulations (EAR), Defense Industrial Base firms pursuing CMMC Level 2 or higher certification, and federal agencies that need FedRAMP High Impact authorization for their cloud workloads.

Specific sectors where GCC High is common include aerospace and defense (manufacturers of aircraft, spacecraft, weapons systems, and related components), advanced manufacturing (companies producing materials or parts), defense technology (firms building cybersecurity tools, communication systems, or classified software), defense research (universities and labs conducting DoD-funded work), and military healthcare (organizations managing health records for active-duty personnel or veterans). The common thread is the regulatory obligation, not the organization's size or revenue. A 50-person subcontractor making circuit boards for a defense program has the same GCC High requirement as a large prime contractor if both handle CUI under a DFARS 7012 clause.