This comprehensive directory profiles every major electronic monitoring vendor serving U.S. corrections, pretrial, parole, probation, and community supervision programs. Whether you are an agency evaluating GPS ankle monitor manufacturers for an upcoming RFP or a bail bond company comparing monitoring service providers, this is the most complete industry reference available.
Table of Contents
- Table of Contents — All EM Vendors
- 1. BI Incorporated (GEO Group)
- 2. SCRAM Systems (Alcohol Monitoring Systems)
- 3. SuperCom (PureSecurity)
- 4. Attenti (Allied Universal)
- 5. Track Group
- 6. Geosatis Technology
- 7. Buddi Limited
- 8. Sentinel Offender Services
- 9. Corrisoft
- 10. OmniLink (Numerex)
- 11. Securus Technologies (BLUtag)
- 12. REFINE Technology (CO-EYE)
- 13. Laipac Technology
- 14. Talitrix
- 15. Megastek Electronics
- 16. iTrack
- 17. Shenzhen Guanwei Intelligent Technology
- 18. Trackimo (PowerFleet)
- 19. 3M Electronic Monitoring (Legacy)
- 20. Serco Group
- 21. G4S / Allied Universal
- Electronic Monitoring Vendor Comparison: Key Specifications
- Frequently Asked Questions
- What are the largest electronic monitoring companies in the United States?
- How many electronic monitoring vendors operate in the U.S. market?
- What is the difference between one-piece and two-piece GPS ankle monitors?
- Which GPS ankle monitor has the longest battery life?
- What types of tamper detection do GPS ankle monitors use?
Table of Contents — All EM Vendors
- BI Incorporated (GEO Group)
- SCRAM Systems
- SuperCom (PureSecurity)
- Attenti (Allied Universal)
- Track Group
- Geosatis Technology
- Buddi Limited
- Sentinel Offender Services
- Corrisoft
- OmniLink
- Securus Technologies (BLUtag)
- REFINE Technology (CO-EYE)
- Laipac Technology
- Talitrix
- Megastek Electronics
- iTrack
- Shenzhen Guanwei Intelligent
- Trackimo (PowerFleet)
- 3M Electronic Monitoring (Legacy)
- Serco Group
- G4S / Allied Universal
1. BI Incorporated (GEO Group)
| Headquarters | Boulder, Colorado, USA |
| Parent Company | The GEO Group (NYSE: GEO) |
| Founded | 1978 |
| Key Products | ExacuTrack One (one-piece GPS), ExacuTrack AT (two-piece), LOC8 (legacy), TAD (alcohol), VeriWatch (wrist GPS) |
| Technology | Gen 2/3 — LTE cellular, one-piece and two-piece architectures |
| Tamper Detection | Capacitive/resistive strap sensors (5-15% false alarm rate) |
| Battery Life | 24-48 hours (LTE standalone) |
| U.S. Footprint | Largest U.S. EM provider — estimated 40-50% market share; 40+ states |
BI Incorporated is the dominant electronic monitoring provider in the United States. As a subsidiary of The GEO Group, BI benefits from deeply embedded relationships with federal, state, and county corrections agencies built over four decades. The ExacuTrack One represents their entry into the one-piece GPS market, though many legacy LOC8 two-piece devices remain in active service. BI holds the federal BOP monitoring contract, giving them the largest installed base in U.S. corrections. Industry observers note that BI’s dominance is driven by contract longevity and procurement inertia as much as by technical differentiation.
2. SCRAM Systems (Alcohol Monitoring Systems)
| Headquarters | Littleton, Colorado, USA |
| Parent | Alcohol Monitoring Systems, Inc. (private) |
| Founded | 2003 |
| Key Products | SCRAM GPS (two-piece), SCRAM CAM (alcohol), SCRAM Remote Breath, SCRAM House Arrest, SCRAM IQ (unified platform) |
| Technology | Gen 2 — Two-piece architecture (RF ankle + portable tracking unit) |
| Tamper Detection | Heart rate / PPG sensors (15-30% false alarm rate) |
| Battery Life | 24-48 hours (GPS tracker unit) |
| U.S. Footprint | Second-largest U.S. provider; dominant in alcohol monitoring; 48 states |
SCRAM Systems dominates the alcohol monitoring segment and holds a strong position in GPS tracking through its two-piece architecture. The SCRAM CAM ankle bracelet is the de facto standard for court-ordered continuous alcohol monitoring in DUI/DWI cases. Their GPS solution uses a legacy two-piece design requiring defendants to carry a separate portable tracking unit. The 2025 launch of SCRAM IQ represents an attempt to unify their product ecosystem under a single software platform.
3. SuperCom (PureSecurity)
| Headquarters | Herzliya, Israel (U.S.: McLean, Virginia) |
| Public/Private | Public (NASDAQ: SPCB) |
| Key Products | PureOne (one-piece GPS), PureTrack (two-piece), PureCom (voice), PureMonitor (software) |
| Technology | Gen 3 — One-piece LTE with integrated alcohol detection option |
| U.S. Footprint | Expanding — Kentucky (4 regions), California, others; strong international (Sweden, Finland, Zambia) |
SuperCom has been one of the most aggressive EM vendors in expanding market share internationally. Their PureOne integrates GPS tracking with optional continuous alcohol monitoring. Recent contract wins include a $17M Sweden national EM contract. SuperCom often positions price competitiveness as a key differentiator against larger incumbents.
4. Attenti (Allied Universal)
| Headquarters | Tel Aviv, Israel (U.S. via Allied Universal) |
| Parent | Allied Universal (acquired 2022) |
| Key Products | AT500 (one-piece GPS), AT Smart Series, Beacon Home Units |
Attenti was a pioneer in electronic monitoring technology, originating from the Israeli defense tech sector. The 2022 acquisition by Allied Universal gave Attenti access to the world’s largest security services workforce. Strong European presence in UK and Israel.
5. Track Group
| Headquarters | Naperville, Illinois, USA |
| Founded | 1995 (as SecureAlert) |
| Key Products | ReliAlert XC3 (two-piece GPS), Shadow (one-piece), SecureCuff (RF), ShadowTrack |
| U.S. Footprint | 30+ U.S. states plus Latin America and Australia |
Track Group has built a solid presence in both U.S. and Latin American markets. The ReliAlert XC3 remains one of the most widely deployed two-piece GPS devices. Their Shadow device represents their move toward one-piece architectures. Strong monitoring center operations provide 24/7 support.
6. Geosatis Technology
| Headquarters | Boudry, Switzerland |
| Founded | 2011 |
| Key Products | Geosatis One (one-piece GPS) |
| Battery Life | 48-72 hours |
Geosatis is a Swiss EM technology company positioned as a premium European alternative. Their Geosatis One was among the earliest purpose-built one-piece GPS devices to achieve CE certification. Limited U.S. presence but contracts across Europe and emerging markets.
7. Buddi Limited
| Headquarters | London, United Kingdom |
| Key Products | Buddi Tag (one-piece GPS), Buddi Beacon |
Buddi is the primary GPS tagging provider for the UK Ministry of Justice, giving it one of the largest single-country EM deployments in the world. Originally a personal safety device company, Buddi pivoted to criminal justice and now dominates the UK market.
8. Sentinel Offender Services
| Headquarters | Irvine, California, USA |
| Key Products | GPS ankle monitors, RF house arrest, alcohol monitoring, drug testing |
Sentinel differentiates through a full-service model providing equipment, monitoring center operations, compliance reporting, and defendant management. This turnkey approach appeals to smaller agencies that lack staff for independent monitoring programs.
9. Corrisoft
| Headquarters | Lexington, Kentucky, USA |
| Key Products | GPS ankle monitors, smartphone monitoring app |
Corrisoft has carved a niche emphasizing smartphone-based monitoring alongside traditional GPS ankle devices, recognizing that many low-risk defendants can be supervised through phone-based check-ins.
10. OmniLink (Numerex)
| Key Products | OM210, OM400 (one-piece GPS) — featured in NIJ Market Survey |
OmniLink’s OM210 and OM400 were prominently featured in the NIJ Market Survey. Multiple ownership changes created uncertainty about long-term continuity.
11. Securus Technologies (BLUtag)
| Headquarters | Dallas, Texas, USA |
| Key Products | BLUtag (one-piece GPS ankle monitor) |
Securus is primarily known for inmate communication services, but BLUtag extends their corrections portfolio into community supervision. Cross-selling across Securus’s installed correctional facility base provides a unique distribution advantage.
12. REFINE Technology (CO-EYE)
| Headquarters | Shenzhen, China (U.S.: Denver, Colorado) |
| Founded | 2004 |
| Key Products | CO-EYE ONE (one-piece GPS), ONE-AC (adaptive connectivity), DUO, BLE i-Bracelet, HouseStation, AMClient app |
| Technology | Industry-first adaptive BLE/WiFi/LTE multi-mode connectivity engine |
| Tamper Detection | Fiber-optic (strap + case dual loop) — zero false alarm rate; optional steel cut-resistant strap |
| Battery Life | 180 days (BLE) / 20 days (WiFi) / 7 days (LTE) |
| Weight | 108g — lightest one-piece GPS ankle monitor available |
| Deployment | 200,000+ devices deployed globally across 30+ countries |
REFINE Technology enters the U.S. market with 20+ years of IoT engineering experience and 200,000+ deployed devices globally. The CO-EYE ONE-AC introduces an adaptive connectivity architecture fundamentally different from all other GPS ankle monitors: rather than running continuous GNSS + LTE (draining batteries in 24-72 hours), the device switches between BLE, WiFi, and LTE modes based on environment, extending battery life to 180 days in BLE mode. Fiber-optic tamper detection eliminates the 15-30% false alarm rates of PPG and resistive sensors.
13. Laipac Technology
| Headquarters | Richmond Hill, Ontario, Canada |
| Key Products | S911 Bracelet Locator ST — featured in NIJ Market Survey |
Laipac supplies OEM GPS tracking hardware to monitoring companies. Their S911 was featured in the NIJ Market Survey and represents a budget entry point for smaller providers.
14. Talitrix
Shenzhen-based manufacturer competing primarily on price in developing markets and OEM supply chains.
15. Megastek Electronics
Diversified Shenzhen GPS tracking manufacturer producing everything from pet trackers to ankle monitors, targeting budget-conscious markets.
16. iTrack
GPS monitoring service provider sourcing devices from OEM suppliers and offering complete monitoring services to agencies and bail bond companies.
17. Shenzhen Guanwei Intelligent Technology
Export-focused OEM manufacturer of electronic monitoring hardware, primarily serving Asian and African markets.
18. Trackimo (PowerFleet)
Now part of PowerFleet, primarily operates in consumer and fleet tracking markets with some corrections applications.
19. 3M Electronic Monitoring (Legacy)
3M’s WMTD was among the first one-piece GPS ankle monitors (featured in NIJ Market Survey). 3M has since exited the EM hardware market, though legacy devices remain in some jurisdictions.
20. Serco Group
Major UK government contractor operating electronic monitoring programs for the Ministry of Justice, procuring hardware from vendors like Buddi.
21. G4S / Allied Universal
Allied Universal acquired both G4S and Attenti, creating the world’s largest security services company with integrated EM capabilities across multiple countries.
Electronic Monitoring Vendor Comparison: Key Specifications
| Vendor | Architecture | Weight | Battery (LTE) | Multi-Mode | Tamper | U.S. Market |
|---|---|---|---|---|---|---|
| BI Incorporated | One/Two | ~220g | 24-48h | No | Capacitive | Dominant |
| SCRAM Systems | Two-piece | ~198g | 24-48h | No | PPG | Major |
| SuperCom | One-piece | ~180g | 24-48h | No | Resistive | Growing |
| Geosatis | One-piece | ~165g | 48-72h | No | Resistive | Limited |
| Track Group | Two-piece | ~200g+ | 24-72h | No | Resistive | Strong |
| Buddi | One-piece | ~160g | ~48h | No | Capacitive | Minimal |
| REFINE (CO-EYE) | One-piece | 108g | 7 days | BLE+WiFi+LTE | Fiber Optic | Emerging |
Specifications from publicly available vendor data and NIJ Market Survey. Battery life in LTE standalone mode. Last updated April 2026.
Frequently Asked Questions
What are the largest electronic monitoring companies in the United States?
The two largest electronic monitoring companies in the United States are BI Incorporated (a subsidiary of The GEO Group) and SCRAM Systems (Alcohol Monitoring Systems, Inc.). Together they serve the majority of U.S. corrections, pretrial, and community supervision programs. Other significant vendors include SuperCom, Attenti (Allied Universal), Track Group, and Sentinel Offender Services.
How many electronic monitoring vendors operate in the U.S. market?
Approximately 20-25 companies actively sell or service GPS ankle monitors and electronic monitoring equipment in the U.S. market, ranging from large publicly-traded corporations to specialized OEM manufacturers and regional service providers.
What is the difference between one-piece and two-piece GPS ankle monitors?
One-piece GPS ankle monitors integrate all components (GPS, cellular, battery, sensors) into a single ankle-worn device. Two-piece systems use a separate ankle tag paired with a portable tracking unit the defendant must carry. One-piece designs eliminate the risk of lost tracking units but historically faced battery constraints.
Which GPS ankle monitor has the longest battery life?
REFINE Technology’s CO-EYE ONE-AC achieves 7 days in LTE mode, 20 days in WiFi-directed mode, and up to 180 days in BLE-connected mode through its adaptive multi-mode connectivity architecture.
What types of tamper detection do GPS ankle monitors use?
The three main types are resistive/capacitive sensors (5-15% false alarm rate), PPG/heart rate sensors (15-30% false alarm rate), and fiber-optic detection (zero false alarm rate).
