EXHIBIT 21

Subsidiaries of Numerex Corp.

Cellemetry, LLC

Cellemetry Services, LLC

I-3G, LLC

NextAlarm, LLC

Numerex Government Services, LLC

Numerex International Limited

Numerex Solutions, LLC

Omnilink Systems, Inc.

Orbit One Communications, LLC

uBlip, Inc.

Uplink Security, LLC

VoiceDataWare, Inc.

Each of our subsidiaries is owned directly by Numerex Corp.