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Ignition interlock in Tennessee

In Tennessee, a court orders an interlock as part of a restricted license after a DUI, and how long you keep it depends on the length of your revocation. The Tennessee Dept. of Safety and Homeland Security runs the Ignition Interlock Program, which lists six approved manufacturers.

Checked Oct 23, 2026Sources
Required after a first conviction
First offense, to drive during the post-conviction suspension
yes
First offense, as a penalty or to get the license back
no
Repeat offense, as a penalty or to get the license back
no
IIHS, October 20261

    165 locations in Tennessee from the companies' own locators. Distances are straight-line; call to confirm the location services your device.

    Each dot is a service location listed by an interlock company. Orange rings mark your search.Company locators, Oct 2026

    Who has to install one in Tennessee

    Your situationInterlockHow longLaw
    First DUI, BAC 0.08% or higher, or alcohol plus drugsRequiredNot statedT.C.A. 55-10-425 (eff. Jan 1, 2023; 'Lexis' printout hosted by TN Dept. of Safety)2
    First DUI with a child under 18 in the vehicle or an accidentRequiredNot statedT.C.A. 55-10-425 (eff. Jan 1, 2023; 'Lexis' printout hosted by TN Dept. of Safety)2
    First DUI, none of those factors applyCourt decidesNot statedT.C.A. 55-10-425 (eff. Jan 1, 2023; 'Lexis' printout hosted by TN Dept. of Safety)2
    First DUI, court makes no findings on the department formRequired by defaultNot statedT.C.A. 55-10-425 (eff. Jan 1, 2023; 'Lexis' printout hosted by TN Dept. of Safety)2
    Second DUI, driving on a restricted licenseRequiredEntire 2-year revocationsafetysupport.tn.gov3
    Third DUI, driving on a restricted licenseRequiredEntire 6-year revocationsafetysupport.tn.gov3

    A judge can order an interlock in other cases too. Your court order or DMV letter is what binds you.

    Where each company can install in Tennessee

    You'll go back to the same company's locations for service for the whole order, so check that one is close to where you live and work before you book.

    Locations as each company lists them on its own locator (Smart Start, Intoxalock, LifeSafer, RoadGuard), pulled Oct 2026. Some shops serve more than one company. Alcohol Detection Systems doesn't publish a locator we could read.

    Interlock companies approved in Tennessee

    Also on the Tennessee list
    • Simple Interlock

    From the state's approved list (read it). Use a company on this list, or the install won't count. 12-month figures are lease, install and removal from each company's filed or published fee schedule, not Tennessee prices; see how we add them up.

    How much an interlock costs in Tennessee

    Estimated total for your order

    1. LifeSafer
    2. RoadGuard
    3. Intoxalock
    4. Smart Start

    Lease times the months you pick, plus install, removal and any enrollment fee, from each company's filed or published schedule (New York filing, Feb 2025; New York filing, 2021; New York filing, Feb 2021; New York filing, Apr 2025). Tennessee prices can differ; calibration visits and lockout fees come on top.

    If you can't afford it

    If a court finds you indigent, a manufacturer cannot refuse you service as long as money is available in the Electronic Monitoring Indigency Fund, which the Tennessee Dept. of Treasury administers.

    Financial help in other states

    The rules in Tennessee

    Program run by
    The Tennessee Dept. of Safety and Homeland Security runs the Ignition Interlock Program. Its manufacturer page lists six approved manufacturers accepting new customers.4
    Approved manufacturers
    The six approved manufacturers are Alcohol Detection Systems, Intoxalock, LifeSafer, RoadGuard Interlock, Simple Interlock and Smart Start. The state's list was last updated August 11, 2026.5
    License you get
    You drive on a restricted driver license with an ignition interlock restriction. A license without the restriction comes from a Driver Services Center once you finish the program.6
    How long
    The usage period is 365 consecutive days or the entire revocation, whichever is longer. Removal also requires the final 120 consecutive days to be violation-free.7
    State fees
    The state charges a $12.50 administrative fee per new user at installation and again each year, which the manufacturer collects and passes along. Caps on manufacturer charges include $75 an hour for installation (up to 3 hours), $125 a month for lease, monitoring and maintenance, and $75 for removal.8
    Help paying
    If a court finds you indigent, a manufacturer cannot refuse you service as long as money is available in the Electronic Monitoring Indigency Fund, which the Tennessee Dept. of Treasury administers.9
    What the fund covers
    Treasury can pay for installation, lease, maintenance and removal through the Electronic Monitoring Indigency Fund. The court paperwork is the Uniform Affidavit of Indigency.10
    Getting it removed
    After 365 days and the final 120 violation-free days, the manufacturer runs a compliance review and sends a Certificate of Compliance to the state. Once the state approves, you pick up an unrestricted license at a Driver Services Center and give a copy to the manufacturer to schedule removal, so the device stays in until you have that license.11
    Violations
    Violations include removing the device early, going 30 days without service, tampering or circumvention, a start attempt above .020 BrAC, a failed random retest above .020 and a skipped retest. Removal or tampering can restart the 365-day clock, and a photo-confirmed high-BrAC or missed-test violation in the final 120 days can add 120 days. A dispute process exists.12
    Random retests
    The device asks for random retests while you drive. A BrAC above 0.02% or a skipped retest counts as a violation.13
    Camera
    State rules define a camera feature on the device. Violations have to be confirmed by photo before they can lead to a 120-day extension.14
    Driving for work
    State law makes no exception for commercial vehicles or motorcycles. The device may go in a non-commercial company vehicle if your employer agrees.15

    Questions about interlocks in Tennessee

    How long do you have to have an interlock in Tennessee?

    At least 365 consecutive days or the entire revocation period, whichever is longer. Revocation runs 1 year for a first DUI, 2 years for a second, 6 years for a third and 8 years for a fourth or later. Before the device comes out, the final 120 consecutive days also have to be free of violations.7

    How much does an ignition interlock cost in Tennessee?

    Tennessee caps what manufacturers can charge: $75 an hour for installation (up to 3 hours), $125 a month for leasing, monitoring and maintenance, and $75 for removal. The state also adds a $12.50 administrative fee at installation and each year. A permanent lockout reset is capped at $50 and a temporary lockout code at $25.8

    Can you get help paying for an interlock in Tennessee?

    Possibly. If a court finds you indigent, a manufacturer cannot refuse you service as long as money is available in the Electronic Monitoring Indigency Fund. The Tennessee Dept. of Treasury administers that fund, and the indigency finding comes from the court, so the process starts with your case.9

    How do you get an interlock removed in Tennessee?

    Removal depends on compliance. After 365 days and the final 120 violation-free days, the manufacturer reviews your record and sends a Certificate of Compliance to the state. Once approved, you get an unrestricted license at a Driver Services Center and give the manufacturer a copy to schedule removal. Keep the device in until you have that license.11

    What happens if you fail a test or violate the interlock rules in Tennessee?

    It depends on the violation. Removing the device or tampering can restart the 365-day clock. A photo-confirmed start attempt or random retest above .020, or a skipped retest, in the final 120 days can extend the requirement by 120 days. A dispute process exists if you think a violation was recorded wrongly.12

    Can you drive a work vehicle with an interlock in Tennessee?

    The device can go in a non-commercial company vehicle if your employer agrees. Tennessee law allows no exceptions for commercial vehicles or motorcycles, so those do not get relief from the interlock requirement. Talk with your employer before installation if you drive a company vehicle.15

    Related guides

    InterlockCompare is independent and doesn't make, sell or install interlocks. Not legal advice.

    Sources

    1. Tennessee: first offense, post-conviction suspension: yesiihs.org/research-areas/alcohol-and-drugs/alcohol-interlock-laws-by-state
    2. the person shall be required by default to install and use a functioning ignition interlock devicesafetysupport.tn.gov/hc/en-us/article_attachments/25742000285971
    3. the Ignition interlock is required for the entire length of the DUI revocationsafetysupport.tn.gov/hc/en-us/articles/25738453872659-How-long-do-I-have-to-have-an-igniti
    4. six (6) approved ignition interlock manufacturers accepting new customerssafetysupport.tn.gov/hc/en-us/articles/25737403257235-Finding-a-Manufacturer-Service-Cente
    5. Last Updated: August 11, 2026safetysupport.tn.gov/hc/en-us/articles/25737403257235-Finding-a-Manufacturer-Service-Cente
    6. Visit a Driver Services Center to obtain a license without the interlock restriction. (removal article)safetysupport.tn.gov/hc/en-us/articles/25739709774099-Ignition-Interlock-Device-Removal
    7. "Ignition interlock usage period" means a three-hundred-sixty-five-consecutive-day period or the entire period of the person's driver license revocation, whichever is longersafetysupport.tn.gov/hc/en-us/article_attachments/25742000285971
    8. not to exceed a total of one hundred and twenty-five dollars ($125.00) per month for leasing, monitoring, and maintenance of BAIIDstn.gov/content/dam/tn/safety/documents/Rules_of_Ignition_Interlock.pdf
    9. shall not be refused service by a manufacturer as long as funds are available in the Electronic Monitoring Indigency Fundtn.gov/content/dam/tn/safety/documents/Rules_of_Ignition_Interlock.pdf
    10. pay for these services: Installation, Lease, Maintenance, Removalsafetysupport.tn.gov/hc/en-us/articles/25741957620883-What-if-I-can-t-afford-the-interlock
    11. Do not remove the device before you have your unrestricted license.safetysupport.tn.gov/hc/en-us/articles/25739709774099-Ignition-Interlock-Device-Removal
    12. may result in a 120 day extension of the time you are required to maintain the interlock.safetysupport.tn.gov/hc/en-us/articles/25739673706643-What-is-a-Violation
    13. Fail a random retest with a BrAC in excess of 0.02%tn.gov/content/dam/tn/safety/documents/Rules_of_Ignition_Interlock.pdf
    14. These violations must be confirmed by photo.safetysupport.tn.gov/hc/en-us/articles/25739673706643-What-is-a-Violation
    15. No exceptions are allowed under current state law for commercial vehicles and motorcycles to have an interlock device.safetysupport.tn.gov/hc/en-us/articles/25738091544211-What-if-I-drive-for-work-but-need-an