Guardian Interlock Review (2026): Costs, Free-Install Offers & Fine Print
Guardian competes almost entirely on upfront cost. It advertises free installation, a $0 first payment and no enrolment fee — which can genuinely save a few hundred dollars at signup, if the offer applies where you live. The monthly rate is where the money actually is, and that’s published as a wide range.
If cash at signup is the constraint — and for a lot of people just out of a DUI it is — Guardian’s zero-upfront structure is the most useful offer in the market. Read the geography, though: the headline savings claim is footnoted to Colorado, New Mexico and California only. Over a full term the monthly lease matters far more than the install fee you saved.
Call for a free quoteGuardian at a glance
| Coverage | Nationwide service-center network ⚠ count not published |
| Installation | Advertised at $0 |
| First payment | Advertised at $0, with no enrolment fee |
| Upfront savings claim | Marketed as over $250 — footnoted valid in Colorado, New Mexico and California only |
| Monthly lease | $50–120 generally |
| Daily equivalent | Company FAQ says around $2 a day on average; its Alabama page says about $3 a day |
| Booking | Online quote and scheduling in about five minutes; same-day appointments available |
| Install appointment | About two hours, including device training |
| Corporate entity | Listed as a related business of LMG Holdings, LLC (LifeSafer) on BBB ⚠ verify |
What Guardian costs
Guardian’s pitch is that you start at zero. That’s real, but the published monthly range is as wide as anyone’s, and over 24 months the lease is where nearly all the money goes.
| Installation (one time) | $0 advertised |
| First payment | $0 advertised |
| Enrolment fee | None advertised |
| Monthly lease | $50–120 |
| Calibration | ⚠ Not separately published — ask |
| Removal | ⚠ Not published — ask |
Monthly lease only, at the published range, assuming the $0 installation offer applies to you. Excludes calibration, state program fees and removal. If the promotion doesn’t cover your state, add installation at market rates of roughly $70–150.
- Whether the free-installation offer applies in your state — the headline savings claim is footnoted to three states
- Your state’s actual monthly rate, since the published range spans more than double
- Whether a deposit is required; a competitor’s comparison page claims Guardian may ask for one ⚠ verify directly
- Calibration cost and interval, which aren’t published
- The removal fee
- Whether the $0 first payment is a waiver or a deferral added to a later bill
Pros and cons
- Zero advertised upfront cost — installation, first payment and enrolment
- Online quote and scheduling in about five minutes
- Same-day appointments available
- Compact device; the install appointment includes training
- The headline savings figure is footnoted to three states only
- Calibration and removal costs aren’t published
- Published monthly range is wide, and its own FAQ and state pages give different daily figures
- Likely shares a corporate parent with LifeSafer, so it may not be a true independent alternative ⚠
How it works day to day
Testing
A breath sample starts the vehicle, with random retests while driving. Guardian markets one of the smaller handsets on the market, which matters more than it sounds when the device lives on your dashboard for a year or two.
Service centers and appointments
Installation takes about two hours and includes a full training session. Avoid alcohol for 24 hours beforehand and skip mouthwash — an alcohol reading at install is an avoidable bad start.
Paying
Guardian’s FAQ notes that payment is generally preferred at the service center at the time of your installation or monitoring appointment. Clarify whether you’re paying the shop, the company, or both.
Should you choose Guardian?
Is Guardian approved in your state?
Guardian is certified in many states but not all. Check your state’s certified-vendor list before signing — an unapproved device won’t satisfy your order.