The Massachusetts ELMO Unit phone number is (978) 365-2970, with a toll-free alternative at (866) 490-1166. Both lines are staffed 24 hours a day, 7 days a week, every day of the year. The unit sits in Clinton and is run by the Massachusetts Probation Service under the Office of the Commissioner of Probation.1Mass.gov. Learn about the Electronic Monitoring Program
Use either number for device malfunctions, alert resolutions, schedule questions, and any other monitoring issue. If something goes wrong with your GPS unit or remote breath device outside regular court hours, these lines are the only way to get it on the record before it turns into something larger.2Mass.gov. Massachusetts Probation Service Programs and Initiatives
Older paperwork and third-party websites sometimes list different numbers. The two above come directly from the Massachusetts Probation Service and are the current lines.
What to Have Ready Before You Call
The dispatcher needs to pull your file fast, especially when an alert is live. A few seconds of preparation on your end saves a long call that leaves the alert sitting in the system.
The single most important piece of information is your Probation Central File (PCF) number. This is the identifier the Massachusetts Probation Service assigned to your case, and you can find it on intake paperwork from your court appearance or probation office. The dispatcher uses it to locate you in the statewide database. Without it, verification takes significantly longer.
You should also know the name of your assigned Probation Officer or Parole Officer. Then be ready to describe the specific issue in plain terms: a strap alarm, a low-battery warning, a signal loss notification, an accidental bump, or something else. If the call is about a schedule change your officer already approved, have the dates, times, and locations written down so the dispatcher can log them exactly.
What Happens on the Call
The dispatcher asks for your PCF number and your supervising officer’s name, then cross-references that against the live tracking system. This identity check runs every time, even for repeat callers. Once your record is open, the dispatcher reviews the issue and takes the right action, which can range from logging an explanation for a routine alarm to flagging a field officer about something more serious.
Depending on what the device is reporting, the dispatcher may walk you through a reset, mark the alert resolved, or tell you to stay put and wait for your officer to follow up. When an alert is really a technical glitch rather than a violation, getting that documented through the call is what keeps it from becoming a problem in court later.
Why Calling Promptly Matters
When a GPS device registers an entry into a restricted area or any other triggering event, ELMO staff first try to reach the person by phone. Many alerts get cleared this way, particularly those caused by GPS drift, signal interference, or an approved schedule that was not updated in the system.
If staff cannot reach you or cannot resolve the alert on the phone, the matter escalates. Staff may notify the local police department and contact your supervising Probation Officer or the Warrant Management Unit. A supervisor can issue an arrest warrant, or the Probation Officer can file a Notice of Probation Violation and Hearing and ask the court to issue one.1Mass.gov. Learn about the Electronic Monitoring Program
Remote breath alcohol monitors follow the same protocol. A missed test or a positive reading generates an alert that goes straight to the ELMO Unit and triggers the same escalation steps as a GPS boundary violation.1Mass.gov. Learn about the Electronic Monitoring Program
The practical takeaway is simple: when something is wrong with the device or your location data, you want to be the one making the call, not the person a dispatcher is trying to reach.
Common Reasons People Call
Low battery. Most GPS ankle units need roughly 1 to 2 hours of charging daily. A low-battery warning usually shows as a flashing red light, and some devices vibrate or beep as the battery gets critically low. If the battery dies entirely, the device stops transmitting location data, and the ELMO Unit sees that as a signal loss alert that can look identical to someone cutting the device off. Charge immediately, then call to explain.2Mass.gov. Massachusetts Probation Service Programs and Initiatives
Signal loss in a known dead zone. GPS can be unreliable in basements, parking garages, and large industrial buildings. If you regularly work or live in a weak-signal area, raise it with your Probation Officer before it generates a string of false alerts. It is easier to get ahead of the pattern than to explain repeated signal loss notifications after the fact.
Accidental damage. A cracked casing or a loose strap you did not cause still produces an alert that looks the same as deliberate tampering. Call the ELMO Unit right away and document what happened so your Probation Officer has the full picture before drawing conclusions.3General Court of Massachusetts. Massachusetts General Laws Chapter 265 Section 47
Schedule and location questions. If your officer approved a change to your allowed hours or locations and you are unsure whether it was entered into the system, calling to confirm is faster than hoping an unentered change does not trip an alert later.
Whatever the reason, both numbers reach the same unit, both are live at all hours, and both work equally well. Save them in your phone before you need them.