ISS stands for "Ignition Interlock System" and it means your license comes with a requirement to install a device in your vehicle
An ISS restriction on your driver's license tells you and law enforcement that you are required to have an ignition interlock device installed in any vehicle you drive. This device prevents your car from starting if it detects alcohol on your breath. You will see "ISS" printed on your license itself, usually in the restrictions section or on the back.
The restriction is almost always the result of a DUI or DWI conviction, though the exact rules vary by state. Some states impose it after a first offense; others only after a second or subsequent conviction. A few states make it optional for first-time offenders but mandatory for repeat offenders.
The device stays in your vehicle for a set period — typically six months to three years, depending on your state and the details of your case. During that time, you can drive legally, but only if the interlock is installed and functioning.
Key Takeaways
- ISS means you must install an ignition interlock device in any vehicle you operate, or you cannot legally drive.
- The restriction is imposed by the court as part of a DUI or DWI sentence and appears directly on your physical license.
- You are responsible for paying the installation and monthly monitoring fees, which typically range from $60 to $150 per month depending on your state and provider.
- Driving a vehicle without the device installed while ISS is on your license is a separate criminal offense in most states.
- The restriction remains in place for the full period set by the court, even if you move to another state.
How the ignition interlock device works
The device is a small breathalyzer unit wired into your vehicle's ignition system. Before you can start the engine, you blow into the mouthpiece. If the device detects no alcohol or alcohol below your state's threshold (usually 0.02% blood alcohol content), the car starts normally.
If alcohol is detected above the threshold, the engine will not start. The device also records the attempt and the result. Some devices require you to provide breath samples at random intervals while driving — if you fail to do so or fail the test, the device may log a violation, honk the horn, or flash the lights to alert you.
You do not own the device. A certified vendor installs it, monitors it, and removes it when your restriction period ends. You pay a monthly fee for this service, and you are responsible for keeping the device clean and in working order.
Who installs the device and what it costs
Your state's Department of Motor Vehicles or the court will provide you with a list of certified interlock vendors in your area. You must choose one from that list — you cannot use an uncertified provider. Common vendors include SCRAM, Alcohol Monitoring Systems (AMS), and Draeger, though availability depends on your state and county.
Installation typically costs $100 to $300 as a one-time fee. Monthly monitoring and lease fees range from $60 to $150, depending on the vendor and your state. Some states cap the fee; others do not. You also pay for removal when the restriction ends, usually $50 to $100. If the device malfunctions or you miss a scheduled service appointment, additional fees may explore.
A few states offer reduced fees or waivers for people with financial hardship, but you must request this through the vendor or the court. Do not assume the fee is waivable — contact your vendor directly to ask.
What happens if you drive without the device installed
Driving a vehicle without an ignition interlock while ISS is on your license is a separate criminal offense. Penalties vary by state but typically include fines of $500 to $1,000, additional jail time, license suspension, and an extended interlock requirement.
The device logs every time someone attempts to start the vehicle, so the vendor and the court know if you have been driving an unequipped car. These violations are reported to the court automatically, and you may be called back for a hearing.
If you need to drive a vehicle that does not belong to you — a rental car, a borrowed vehicle, or a company car — you must have the interlock installed in that vehicle too, or you cannot legally drive it. Some rental companies will not allow interlock installation on their vehicles, which means you cannot rent from them during your restriction period.
How long the restriction stays on your license
The length of the ISS requirement is set by the court at sentencing and depends on your state's law and the specifics of your case. A first DUI conviction typically results in six months to one year of interlock requirement. A second or subsequent conviction usually means one to three years.
The clock starts when the device is installed, not when you are convicted. If there is a delay between sentencing and installation, that delay does not count toward your restriction period.
Once the period ends, you contact your vendor to schedule removal. The device is uninstalled, and your license restriction is lifted. You should receive written confirmation from the vendor and the court that the device has been removed and the restriction is no longer active.
Moving to another state with an ISS restriction
If you move out of state while ISS is on your license, the restriction follows you. Your new state will recognize the restriction from your original state, and you must continue to maintain the interlock device in any vehicle you drive.
You will need to transfer your license to your new state at some point, but the ISS restriction will carry over to your new license. The device must remain installed for the full period set by the original court, even if your new state has different interlock laws.
Some states have reciprocal agreements that allow you to satisfy an out-of-state interlock requirement by using a certified vendor in your new state. Contact your new state's DMV to confirm where you can have the device serviced and monitored.
Removing the ISS restriction from your license
The restriction is removed automatically once the device is uninstalled and the vendor reports completion to the court and DMV. You do not need to do anything except schedule the removal appointment with your vendor.
After removal, you should receive a new license without the ISS restriction. If your current license still shows the restriction after the device has been removed and reported, contact your state's DMV to request an updated license. There may be a small fee for the replacement license.
In some cases, you may be able to request early removal of the ISS requirement if you can demonstrate to the court that you have complied with all conditions and pose no further risk. This is called a "hardship waiver" or "early termination" and is not automatic — you must petition the court and the judge must approve it. Rules and likelihood of approval vary significantly by state and judge.
Frequently Asked Questions
Can I drive someone else's car if I have ISS on my license?
No, not unless that vehicle has an interlock device installed. You cannot legally operate any vehicle without the device while the restriction is active. This applies to borrowed cars, rental vehicles, and company cars. If the vehicle does not have the device, you cannot drive it.
What if the interlock device malfunctions or gives a false positive?
Contact your vendor when ready. Malfunctions should be documented and reported. If the device fails a breath test when you have not consumed alcohol, ask the vendor to review the device's calibration and service record. Keep records of all service visits and any disputes. If violations are logged due to a malfunction, you can petition the court to have them removed, but you must have documentation from the vendor.
Do I have to pay for the interlock if I cannot afford it?
Some states and vendors offer reduced fees or payment plans for people with financial hardship, but this is not automatic. You must contact your vendor or the court and request a hardship review. Bring proof of income and expenses. If you cannot afford the device, you cannot legally drive, so addressing this quickly is important.
Will the ISS restriction show up on background checks?
The DUI conviction itself will show on background checks. The ISS restriction on your license is a public record and may be visible to employers or others who check your driving record. The restriction itself does not appear on criminal background checks, but the underlying DUI conviction does.
Can I get the restriction removed early?
You can petition the court for early removal, but approval is not may provide and depends on your state's law and the judge's discretion. You typically must demonstrate full compliance with all conditions and sometimes complete an alcohol education program. Contact the court that sentenced you to ask about the process in your jurisdiction.