Discreet Affordable Reliable

FREE Installation*

We know you have already put a lot of money into your DUI so we offer free installation and all inclusive maintenance fees

*Some restrictions apply. Participating locations only. Not available with all makes/models.

Customer Service

We offer 24/7 customer service when you call 800-880-3394. Operators are there to assist you in both English and Español

Financial Assistance

Unable to afford your interlock device? We have staff standing by to help you navigate the TN Indigent Program

#1 Alcohol Monitoring Devices

SmartStart IID

smart start of tn ignition interlock device

Believe it or not, all Ignition Interlock Devices (IIDs) are not created equal. While some car breathalyzer brands boast affordability, quality and safety are often overlooked. Every product that Smart Start manufactures is not only affordable but also designed with your safety and usability as our main objective. In fact, Smart Start thoroughly tests every interlock device to ensure that it exceeds the National Highway Traffic Safety Administration (NHTSA) standards, keeping you safe while you travel. The sleek and discreet design fits comfortably anywhere in your vehicle. Expect only the most accurate results so you never have to worry about false positive readings. Since 1992, millions of customers have trusted Smart Start for the best Ignition Interlock Device nationwide.

Simple Interlock IID

Simple Interlock of TN

Simple Interlock knows that you want to get back on the road, so we’ve made the process simple with the cheapest car breathalyzer device. We have one ignition interlock device (IID) that can be programmed to meet your program’s needs. Pricing is simple and up-front; we’ll charge you one flat fee with no hidden or erroneous additions. No matter how you contact us—by phone, email, or chat—you’ll reach a real, live human being who can answer your ignition interlock device questions and walk you through the process.

*Not available at all locations


SmartMobile Device

Not every client needs continuous monitoring;  SmartMobile™ is the perfect alternative.

SmartMobile™ is NHTSA certified, alcohol specific, fuel cell technology that provides court admissible data. It is GPS enabled and equipped with a facial detection camera.

SmartMobile™ features include:

  1. Half the price of alternative monitoring devices with convenient payments
  2. Completely customizable test windows compatible with client work schedules, as well as on-demand testing
  3. Powered by Verizon; no docking station, landline, internet or smartphone needed
  4. All normal activities can be performed without worrying about damaging the device
  5. Instant violation alerts via SmartWeb™, the best case management software available


Interlock Xpress-Clarksville

Servicing Wednesdays 8am- 5pm

Interlock Xpress-Franklin

Servicing Tuesdays and Thursdays 8am-5pm

Interlock Xpress-Gallatin

Servicing Mondays and Thursdays 8am-5pm

Interlock Xpress-Murfreesboro

Servicing Mondays and Wednesdays 8am-5pm

Interlock Xpress-Nashville

Servicing Tuesdays 8am-5pm and Fridays 9am-2pm

Smart Start of TN-Chattanooga

Servicing Monday-Friday, 8am-5pm

Smart Start of TN-Halls

Smart Start of TN-Knoxville

Smart Start of TN-Johnson City

Smart Start of TN-Bartlett

Smart Start of TN-Collierville

Smart Start of TN-Sevierville

Plaza Electronics

Customs Tint & Off Road

G-Man Services

Servicing Monday-Friday 8am-2pm, Saturday 8am-12pm

Audio Works

PDR Specialist

North Main Audio

Servicing Tuesday and Thursday, closed Wednesdays

Dennis Mitchell Automotive Center


Interlock Xpress @ JNR Electronics

Servicing Tuesdays, Thursdays and Fridays 9am-5pm

Maryville-Coming Soon!

Shaffer Muffler Shop

Hilltop Auto & Towing


Manchester-Coming Soon!

Scottie Brown Auto

Wood's Glamorous Ridez

Lexington-Coming Soon!

Harriman-Coming Soon!

Soddy Daisy-Coming Soon!

J&J Complete Car Care

McMinnville-Coming Soon!

Shelbyville-Coming Soon!

Ripley-Coming Soon!

Covington-Coming Soon!

Morristown-Coming Soon!

New Johnsonville-Coming soon!

Ashland City-Coming Soon!

DUI Help is Here!

TN Law requires installation of a car breathalyzer for a minimum of 365 days to regain a valid TN Driver License. Smart Start of TN is the leading Ignition Interlock installer in Tennessee. Ready to install your IID? We’re here to help you get back on the road!