Ignition Interlock

As a condition of release on bail, a Magistrate Judge may order a defendant to install an ignition interlock device on any vehicle driven. An interlock device is a deep-lung breath analysis mechanism designed to prevent the operation of a motor vehicle if alcohol is detected in the breath of the vehicle operator.

How to Pay Interlock Fee

No Cash or Personal Checks.

  • In Person
    • Pretrial Services
      First Floor, Justice Center
      405 Martin Luther King Jr. Street
      Georgetown, TX 78626
  • Mail
    • Williamson County Pretrial Services
      405 Martin Luther King Boulevard
      Box 19
      Georgetown, Texas 78626.
  • Online (follow these instructions)
    • Choose Payment Type "Ignition Interlock Fee" from drop-down menu
    • Sheriff's Office Number (SO#) - the number assigned to the defendant while in custody.

Include defendant's Name, DOB and Sheriff's Office Number (SO#) - the number assigned to the defendant while in custody.

Money Orders and Cashier's Checks should be payable to "Williamson County."

Technical Difficulties with the Device

If you have questions regarding basic operation of the device such as physical installation, how to use or manage the device, how to transfer the device from one vehicle to another, physical removal or return of the device, please contact the ignition interlock company.


Defendant may request removal at by emailing ignition. If defendant's case was never assigned to a court. Defendant should notify the PR bonds office immediately by emailing ignition if the case is transferred to other monitoring agency such as probation. Defendant's attorney may request removal by order of the assigned court or magistrate.