An ISS driver license is a restricted license issued by your state's Department of Motor Vehicles when your regular license has been suspended or revoked
ISS stands for Ignition Interlock System. This license allows you to drive only vehicles equipped with an ignition interlock device — a breath-testing machine that prevents the engine from starting if it detects alcohol on your breath. You cannot drive any other vehicle, even if someone else owns it.
Most states issue ISS licenses after a DUI or DWI conviction, though some issue them for other serious traffic violations. The license is temporary and comes with specific restrictions about where, when, and under what conditions you can drive. Once you complete the interlock requirement period, you can petition to have your full driving privileges restored.
Key Takeaways
- An ISS license only permits you to drive vehicles with an installed ignition interlock device, which tests your breath before the engine will start.
- Your state's DMV issues an ISS license after certain convictions, typically DUI or DWI, and specifies how long you must use the device.
- You must pay for the interlock device installation, monthly monitoring fees, and calibration costs — expenses vary by state and service provider.
- Driving a vehicle without an interlock when your license requires one is a separate criminal offense that can result in additional penalties.
- After you complete the required interlock period, you can request that your full license be restored through your state's DMV.
How an ignition interlock device works
The device is a small machine wired to your vehicle's ignition system. Before you start the engine, you blow into the mouthpiece. If the device detects no alcohol or alcohol below the legal limit, the engine starts normally. If it detects alcohol above the threshold, the engine will not turn on.
The device also requires rolling retests — random breath tests while you are driving. If you fail a rolling retest, the vehicle's lights and horn set up to alert you, and the event is recorded. You do not have to pull over when ready, but you must take the test at the next safe opportunity. Failing or refusing a rolling retest counts as a violation of your ISS license terms.
Every 30 to 60 days, you must take the device to a service center for calibration and data read. The service provider records all test results, violations, and attempts to tamper with the device. This data is reported to your state's DMV and may be reviewed by the court.
Who issues an ISS license and when
Your state's Department of Motor Vehicles issues the ISS license, usually after you have completed a DUI or DWI conviction process. The court typically orders the interlock requirement as part of sentencing, and the DMV implements it by issuing a restricted license that permits only interlock-equipped vehicles.
Some states issue ISS licenses automatically after conviction. Others require you to request one from the DMV after your suspension period ends. A few states allow you to request an ISS license when ready after arrest, before conviction, to maintain limited driving privileges during the legal process — but this varies significantly by state.
The length of time you must use an interlock device depends on your state's law and the specifics of your case. First-time offenders typically face 6 to 12 months of interlock use. Repeat offenders or those with high blood alcohol levels may face 2 to 3 years or longer. Your sentencing documents will specify the exact duration.
Costs you will pay for an ISS license
You are responsible for all expenses related to the interlock device. Installation typically costs $100 to $300 per vehicle. Monthly monitoring and maintenance fees range from $50 to $100, depending on your state and the service provider. Calibration visits every 30 to 60 days may cost $10 to $30 each.
If the device detects a violation — a failed breath test, a failed rolling retest, or an attempt to tamper with it — you may face additional fees to reset or service the device. Some states also charge a reinstatement fee when you petition to have your full license restored after the interlock period ends.
These costs add up quickly. Over a 12-month interlock period, you could spend $1,200 to $2,000 or more. Some states offer fee reductions for low-income drivers, but you must request this through the DMV or the court. Ask your local DMV or the service provider about hardship waivers if cost is a barrier.
Restrictions that come with an ISS license
An ISS license is not a regular license with a note attached. It is a separate, restricted license that only permits you to drive vehicles equipped with a functioning interlock device. You cannot drive a rental car, a borrowed vehicle, a company car, or any other vehicle unless it has an interlock installed.
Some states also restrict the hours you can drive or the roads you can use. Your license documents will specify these restrictions clearly. Violating any restriction — driving without an interlock, driving outside permitted hours, or driving outside a permitted zone — is a separate criminal offense that can result in additional fines, jail time, or an extended interlock requirement.
You must also maintain continuous insurance on any vehicle you drive. If your insurance lapses, your ISS license becomes invalid, and driving is illegal. Some insurers charge higher premiums for drivers with interlock requirements, so contact your insurance company before you install a device.
How to request restoration of your full license
After you complete the required interlock period, you do not automatically get your full license back. You must petition your state's DMV or the court that issued the original sentence. The process and timeline vary by state, but generally you will need to submit proof that you have completed the interlock requirement.
Proof typically includes a letter from the interlock service provider confirming that you met all requirements — no violations, all monitoring fees paid, all calibration appointments kept. Some states also require a new written or driving test before restoration. A few states require you to appear before a judge or administrative hearing officer.
Once your petition is approved, the DMV will issue a new, unrestricted license. This usually takes 1 to 4 weeks. You can then have the interlock device removed from your vehicle. The service provider will remove it at no additional charge, though you may be responsible for any damage to the vehicle caused by installation.
What happens if you violate ISS license terms
Violations are recorded by the interlock device and reported to the DMV. Common violations include failed breath tests, failed rolling retests, missed calibration appointments, and attempts to tamper with or bypass the device. Even one violation can trigger consequences.
Depending on your state and the severity of the violation, consequences may include fines, extended interlock requirements, license suspension, criminal charges, or jail time. Driving a vehicle without an interlock when your license requires one is typically treated as a separate criminal offense, not just a license violation.
If you accumulate multiple violations, the court may extend your interlock requirement by months or years. In some cases, the court may revoke your ISS license entirely and return you to a full suspension. This is why it is critical to keep all calibration appointments and follow all restrictions, even if you believe the device is malfunctioning.
Frequently Asked Questions
Can I drive someone else's car if they have an interlock device?
Yes, as long as the device is functioning and you use it correctly. However, you are responsible for any violations recorded on that vehicle's device. If the owner of the vehicle fails to maintain it or tampers with it, you could face violations on your record even though you did not cause them. Before driving someone else's interlock-equipped vehicle, confirm that the device is current on calibration and functioning properly.
What if the interlock device malfunctions and I cannot start my car?
Contact the service provider when ready. They can troubleshoot the device or schedule an emergency service visit. If the device fails due to a defect, the service provider can usually provide documentation that you attempted to use it. Keep records of all service calls. If you miss work or an appointment because of a device malfunction, document this and report it to your DMV — some states may waive certain violations if you can prove the device was faulty.
Do I have to install an interlock in every vehicle I own?
No. You only need an interlock in the vehicles you plan to drive. However, you cannot drive any vehicle without one during your ISS period. If you own multiple cars, you can choose to install the device in only one and drive only that one. If you sell a vehicle with an interlock, the new owner can have it removed at no cost.
Can I get my ISS license early if I have not violated it?
This depends on your state and the court order. Some states allow early termination if you have a clean record during the interlock period. You would need to petition the court or DMV with proof of compliance. Other states have mandatory minimum periods that cannot be shortened. Check your sentencing documents or contact your local DMV to learn whether early termination is possible in your case.
What if I move to a different state while on an ISS license?
Your ISS license is valid only in the state that issued it. If you move, you must obtain a new license from your new state's DMV. Most states recognize interlock requirements from other states and will issue an ISS license that meets your original state's requirements. Contact your new state's DMV before you move to understand the process and any additional requirements.