Ignition Interlock Device Cost
An ignition interlock device (IID) is a breath-alcohol analyzer wired to a vehicle's ignition. The vehicle will not start unless the driver provides a breath sample below the preset limit, and the device requires periodic "rolling" retests while driving. States require IIDs as a condition of restricted driving privileges or reinstatement after certain DUI offenses.
The driver pays the vendor directly. This page collects national cost ranges and the vendors most commonly approved by state agencies. State-specific fee caps, indigent programs, and required durations are on each state page.
National cost ranges
Ranges are the lowest and highest figures published by vendors on their own price pages on the date checked. Actual charges depend on the state program, the vendor, and the vehicle.
| Item | Range | Basis | As of |
|---|---|---|---|
| Installation fee | $50–$250 | Low: RoadGuard ($50–$150); high: Low Cost Interlock ($100–$250). Also stated: Intoxalock $70–$100; LifeSafer $70–$150; ALCOLOCK $70–$150; Guardian $70–$170; Smart Start "as low as" $150. | 2026-08 |
| Monthly lease / monitoring | $50–$150 | Low: LifeSafer, Guardian and RoadGuard each state $50 as the bottom of their range; high: RoadGuard ($50–$150). Also stated: Intoxalock starting at $54.99 (and $60–$90 in its knowledge center); Smart Start "as low as" $59.99; ALCOLOCK $60–$90; Low Cost Interlock $78.76. | 2026-08 |
| Calibration / service visit | $0–$25 | Low: Guardian (states no charge for calibration unless additional servicing is needed); high: Smart Start ("starting from" $25) and LifeSafer ("around" $25). Also stated: Intoxalock about $20 per appointment; Low Cost Interlock typically $20. RoadGuard and ALCOLOCK do not state a separate calibration fee. | 2026-08 |
| Removal fee | $50–$150 | Low: RoadGuard ($50–$150); high: RoadGuard ($50–$150). Low Cost Interlock states a flat $129.50. Intoxalock, Smart Start, LifeSafer, Guardian and ALCOLOCK do not state a removal fee on the pages fetched. | 2026-08 |
| Vendor-stated 12-month total | $1,200–$1,500 | Low and high: Low Cost Interlock, the only vendor that states a program total in its own words. RoadGuard's 2026 blog relays a third-party (JLARC) one-year figure of $2,652 rather than stating its own total. No vendor states a 6-month total. | 2026-08 |
| Set-up / enrollment fee | $0–$40 | Low: Guardian ($0 enrollment fee under its Colorado/New Mexico/California offer); high: Low Cost Interlock ($40). Smart Start lists a one-time enrollment fee without an amount. | 2026-08 |
Sources for these ranges (9)
- RoadGuard Interlock – Interlock Device Cost
- Low Cost Interlock – Ignition Interlock Pricing
- Intoxalock – Understanding the cost of an ignition interlock device
- LifeSafer – Ignition Interlock Device Cost and Pricing
- ALCOLOCK – What Does An Ignition Interlock Device Cost?
- Guardian Interlock – Ignition Interlock Pricing
- Smart Start – Ignition Interlock Device Cost & Pricing
- Intoxalock – Ignition Interlock Device Cost and Pricing
- RoadGuard Interlock – What You'll Actually Pay For An Interlock Device in 2026 (citing a JLARC report)
State fee caps and reduced-cost programs
Examples of states that cap what a vendor may charge or require reduced pricing for drivers who meet a financial-hardship standard. Each links to the official rule.
| State | Rule | Amount / provision | Source |
|---|---|---|---|
| Tennessee | Provider fee caps – Tenn. Comp. R. & Regs. 1340-03-06-.15(3)–(5) | Installation not to exceed $75/hour (3-hour maximum); leasing, monitoring and maintenance not to exceed $125/month; removal not to exceed $75 | Official page |
| Virginia | Maximum offender charges – 24VAC35-60-50(C) | $65 standard installation ($130 hybrid/push-button start); $95 plus applicable taxes per month for calibration/monitoring; $0 removal; $75 change-of-vehicle installation | Official page |
| Kentucky | Provider fee caps and income-based reductions – KRS 189A.340(7) | Installation not to exceed $100 ($130 alternative-fuel or push-button start); monthly fee not to exceed $100; removal not to exceed $30; reset not to exceed $50; missed appointment not to exceed $35; persons at or below 200%/150%/100% of federal poverty guidelines pay 75%/50%/25% of fees | Official page |
| Washington | DOL financial assistance for indigent Ignition Interlock Driver License holders | $80 per month reimbursed to the provider for each service (installation, monthly lease, removal, transfer); must be indigent under RCW 10.101.010; reapply yearly | Official page |
| Kansas | Reduced ignition interlock program costs – K.S.A. 8-1016 | Eligible persons (annual household income at or below 150% of the federal poverty level) pay 50% of program costs | Official page |
| Wisconsin | Reduced IID liability for low-income persons – Wis. Stat. § 343.301(3)(b) | Household income at or below 150% of the federal poverty line: liability limited to one-half of installation cost and one-half of per-day maintenance cost per vehicle | Official page |
What drives the total cost
- State program rules
- Each state sets its own device standards, required service intervals, and reporting obligations. Those requirements determine how often a device must be serviced and therefore how many service visits are billed over the program.
- Program length
- The required interlock period is set by state law and the court or licensing agency. Because most vendors bill monthly, the required duration is the largest single driver of total cost.
- Vendor pricing
- Vendors set their own installation, lease, and removal prices. Some states cap fees or publish approved price schedules; where a state does so, the state page links to that document.
- Indigent or reduced-fee programs
- Some states require approved vendors to offer reduced pricing to drivers who meet a financial-hardship standard defined in statute or rule. Where such a program exists, the state page cites the governing rule.
Interlock vendors on state approved lists
Vendors are listed alphabetically. Inclusion is not an endorsement. Approval is granted state by state; each state page links to the agency list where a vendor's approval can be confirmed.
Vendors that publish no prices on their own sites: Simple Interlock, Alcohol Detection Systems.