Ignition Interlock Device (IID) in California: Terms, Costs & Restricted Licenses

What Is an Ignition Interlock Device?

An ignition interlock device (IID) is a breath-testing device wired into a vehicle’s ignition system. Before the engine will start, the driver must blow into the device and pass a breath-alcohol test. While driving, the device demands random retests at unpredictable intervals — miss one, or fail one, and the device logs it. The device also logs every start attempt, every test result, and every service event, and the installer reports problems to the DMV.

This guide is general legal information, not legal advice. IID terms, eligibility, and restricted-license timing turn on your own conviction history and DMV record — if you are facing a DUI, talk to a California DUI defense attorney, and confirm your own requirements with the DMV before you spend money on installation.

Three things the IID is not:

• It is not a license. An IID in your car does not let you drive. You still need a valid driver’s license or an IID-restricted license, and the DMV must have the restriction on your record before you drive with the device.
• It is not a punishment you can buy your way out of. The term runs in calendar months of compliant installation. Time when you are out of compliance — device removed, service missed, tampering logged — does not count toward the term (VC §23575.3(j)).
• It is not the old 4-county pilot. From 2010 to 2018, IID installation was a pilot in Alameda, Los Angeles, Sacramento, and Tulare counties only. Since January 1, 2019, the statewide program (SB 1046) applies everywhere in California. Any page that still describes the IID program as a 4-county pilot is years out of date.

How a normal day with an IID works. You get in, blow a clean sample, and start the car. Minutes into the drive the device beeps for a rolling retest; you blow again while driving. At the end of the day the device has a log of every sample. Every 60 days at most, you return to the installer for calibration and a data download. That routine — boring, predictable, and fully logged — is the whole point: the state is not watching you drive, it is watching whether you drink and drive.

Who Orders an IID: the Court, the DMV, or Both?

Both — in sequence, and confusing the two roles is how most IID guides go wrong. The court orders the IID as part of the sentence; the DMV administers it afterward. Here is the chain, step by step:

A second, DMV-administered track exists. VC §23573 covers a different population: people convicted of driving on a suspended or revoked license (VC §§14601.2, 14601.4, 14601.5) after prior DUI convictions. There the DMV itself drives the process — it informs you of the requirement and term, you have 30 days to install and file proof, and willful failure to install is a misdemeanor punishable by up to 6 months in county jail or a fine up to $5,000, or both (VC §23573(i)). If your IID order came from a suspended-license conviction rather than a DUI conviction, VC §23573 — not VC §23575.3 — is your statute, and its terms are in the second table below.

A warning about old law in new articles. Older pages quote a court power to order an IID for a first offense for up to 3 years, with heightened consideration at a BAC of 0.20% or more, two or more prior moving violations, or a test refusal. That was the pre-2019 version of VC §23575. Under current law the first-offense court-ordered IID term is capped at 6 months (VC §23575.3(h)(1)(A)(i)). If a page quotes you a 3-year first-offense IID term, it is quoting dead law.

How Long Is an IID Required? The Term-by-Offense Tables

The tables below are the statute, not a summary of law-firm blogs. “Prior” means a separate qualifying conviction within 10 years of the current violation (VC §23575.3(h)(3)). Terms begin once you have filed proof of installation and your privilege is reinstated or an IID-restricted license is issued, and you receive credit for any period you already held an IID-restricted license under VC §13353.6 or §13353.75 (VC §23575.3(h)(4)).

The first-offense fork, stated plainly. For a first non-injury DUI conviction, VC §23575.3(h)(1)(A) gives three alternatives, not one mandatory term: (i) the court may order an IID for a term it sets, not to exceed 6 months from conviction; (ii) you may apply for a restricted license under VC §13352.4; or (iii) you may apply for a restricted license under VC §13352(a)(1) or §13352.1(c). That is why reputable guides disagree about “first DUI = 6 months”: the 6-month figure is the maximum court-ordered term on that path, not a flat mandatory term for every first offender. Your sentencing order controls — read it before you rely on any table.

A footnote on the DMV’s own table. The DMV’s summary table expresses the top cells as “1 or more prior felony convictions → 3 years (non-injury) / 4 years (injury).” The statute’s 48-month cell is narrower: an injury offense with one prior punishable under VC §23550.5. The tables above follow the statute; the DMV’s wording is the summary, not a different rule.

Worked examples. A driver with a second non-injury DUI (one prior) faces a 12-month mandatory IID term — not 6, not 24. A driver with a third DUI that caused an injury and one prior faces 24 months. A driver whose IID order comes from driving on a suspended license after two prior DUI convictions faces 2 years under VC §23573, even if the suspended-license conviction itself involved no alcohol. The statute you are under changes the number — that is why the sentencing order and the DMV’s notification letter, not a blog table, are the documents that decide your term.

The 2033 Date — and Why It Is Not AB 1546

If you have read that “California’s IID rules change in 2033” or that “AB 1546 sets IID terms from 2033,” here is the correction, with the receipts:

• What 2033 actually is: a sunset clause. VC §23575.3(r) and VC §23573(o) each state that the section “shall remain in effect only until January 1, 2033, and as of that date is repealed, unless a later enacted statute, enacted before January 1, 2033, deletes or extends that date.” In plain English: the IID statutes expire on that date unless the Legislature extends them again.
• Who moved the date: AB 366 (Stats. 2025, Ch. 689), effective January 1, 2026, which amended both sections and moved the sunset from January 1, 2026 to January 1, 2033. AB 366 also requires DMV implementation data to the California State Transportation Agency by July 1, 2030 and a legislative report by July 31, 2031 — the Legislature built in a check-up before the next sunset decision.
• What AB 1546 is not: AB 1546 (Stats. 2026, Ch. 444, operative January 1, 2027) rewrites DUI charging tiers — third DUI becomes a wobbler, fourth a wobbler, fifth a straight felony. Its chaptered text contains no IID provision at all: it does not amend VC §23575.3, set IID terms, or set any 2033 operative date. Any page attributing IID rules or a 2033 date to AB 1546 has the two 2025–2026 DUI bills crossed.

One more nuance, for accuracy: AB 366’s chaptered summary says that on January 1, 2033 the law is reinstated to how it read before January 1, 2019 — so the date is a sunset plus a reinstatement of the old pattern, not a cliff after which nobody has ever heard of IIDs. Either way, the Legislature must act before 2033 to keep the current framework alive, and that decision is what the 2030 data report and 2031 legislative report are for.

What the sunset means for you in practice: nothing, right now. If you are ordered to install an IID in 2026, your term runs under the current statutes regardless of the 2033 sunset. The sunset matters to the Legislature’s next decision, not to your installation appointment. Do not let a page use “2033” to suggest your IID requirement starts then, ends then, or disappears then.

How Installation, Calibration, and Reporting Actually Work

Step 1: choose a certified provider. Only a provider certified under VC §13386 may install your device. Installers themselves must hold a Bureau of Automotive Repair (BAR) or Bureau of Household Goods and Services (BHGS) license — you can check a local installer through the Department of Consumer Affairs license search — and the DMV publishes an approved manufacturers and devices list (linked at the end of this guide; certifications change, so check the list rather than trusting a static copy).

Step 2: get it installed and file the proof. The installer wires the device into your vehicle’s ignition, calibrates it, and trains you: how to blow (a steady sample, not a puff), what the retest beeps mean, and what to do if the device locks you out after failed samples. The installer gives you the Verification of Installation (DL 920), which you file with the DMV. The DMV’s 30-day clock in VC §23575.3(d)(1) runs from its notification to you — installation, proof, and the administrative fee are all due inside that window.

Step 3: every vehicle you operate. The restriction covers every vehicle you operate, not just the car you own. A borrowed car, a rental car, and a spouse’s car all need a functioning certified IID before you drive them while restricted — the statute says “any vehicle that the person operates” (VC §23575.3(a)) and “operates” includes a vehicle you do not own (VC §23575.3(o)(2)). There is no “just this once in an unequipped car” exception. The one general carve-out is employer vehicles driven in the scope of employment with an IID-restricted license and a completed DL 923 (see the edge-cases section below).

Step 4: service at least every 60 days. VC §23575.3(f)(1) requires service by the installer at least once every 60 days to recalibrate and monitor the device. This is the figure competitors most often get wrong: pages quoting a 30-day calibration rule are describing other states’ programs or older pilot practice, not current California statute. Your provider may schedule you more often for operational reasons, but the statutory floor is 60 days — and missing service events is itself reportable after three failures (VC §23575.3(f)(2)).

Step 5: the installer reports to the DMV. The installer must notify the DMV if the device is removed, if it indicates an attempt to remove, bypass, or tamper with it, or if you fail three or more times to comply with maintenance or calibration requirements (VC §23575.3(f)(2)). The DMV monitors installation and maintenance throughout the term (VC §23575.3(g)). A failed retest, a missed service, and an early removal are not private matters between you and the shop — they go on your DMV record.

What an IID Costs in California

Here is the honest version of IID costs, which is why this section looks different from competitor pages that print one confident number: California law does not set a dollar price for an IID. Providers set their own standard program costs, and the statute instead fixes what share of that cost you pay, based on your income. Any page that prints a single “official” IID price is inventing it.

The part the statute does fix: your share by income. VC §23575.3(k) requires every certified manufacturer to charge you based on your income relative to the federal poverty level, with the manufacturer absorbing the rest:

To claim a reduced share you must verify income with one of: last year’s federal tax return, the last three months of pay statements, an Employment Development Department unemployment-benefits verification, or CalFresh proof (VC §23575.3(k)(2)). Noncompliance surcharges are yours in full even at a reduced share — the statute says you remain responsible for “any additional costs accrued by the person for noncompliance with program requirements.” A manufacturer that fails to tell you about this schedule faces a civil assessment up to $1,000 (VC §23575.3(l)).

Worked totals (illustrative arithmetic on the ranges above — not quotes). At midpoint rates ($110 installation + $75/month monitoring), provider charges run about $1,010 for a 12-month term, $1,910 for 24 months, and $2,810 for 36 months, before DMV fees and SR-22 costs. At a 10% income share, those provider totals fall to roughly $101, $191, and $281 respectively. Your actual total depends on your provider’s standard program cost — get it in writing, including removal, before you sign.

Getting a Restricted License With an IID

For most drivers, the IID is not the goal — driving legally again is. California gives first-offense DUI drivers two distinct restricted-license paths after an APS suspension, and the IID path is the faster one:

What the IID-restricted application requires. In practice, the DMV expects all of the following before it issues the restriction: a certified IID installed (DL 920 filed), enrollment in the appropriate DUI program (proof-of-enrollment DL 107, or completion DL 101), an SR-22 filing on record, payment of the applicable reissue fee ($125 on the APS track), and clearance of any other suspensions or revocations on your record. You apply at a DMV field office — restricted licenses are issued in person, not online — and you should bring every document, because a missing paper is a second trip. Time you spend on an IID-restricted license under VC §13353.6 or §13353.75 counts toward your later mandatory IID term (VC §23575.3(h)(4)) — the clock you start early is not wasted.

The APS clocks, for completeness. Before any conviction, APS offenders may opt for an IID restriction of up to 4 months (first, non-refusal) or up to 1 year (repeat, non-refusal), with no suspension period if they apply immediately — and that APS IID time may credit toward a later mandatory term if convicted. The APS work/program-only restriction runs up to 5 months in the DMV’s APS table. These are the three clocks behind the “5 months vs 6 months” confusion: court-ordered IID up to 6 months, APS IID up to 4 months, APS work/program up to 5 months — never quote one of those numbers without naming its clock.

Repeat offenders: no single timing figure exists, and this page will not invent one. After a second or later DUI, restricted-license eligibility timing depends on the exact suspensions and revocations on your record, including any refusal history and any outstanding holds. Attorney guides disagree with each other on repeat-offender timing for exactly that reason. Before you pay for installation on a repeat offense, confirm your own eligibility and timing with the DMV — the Driver Safety line is (833) 543-7703 — and bring the DMV’s answer, in writing if possible, to your installer appointment.

Commercial drivers, take note. A CDL holder must downgrade to a non-commercial license to obtain an IID-restricted license (DMV IID page) — an IID restriction does not restore commercial driving privileges, and federal commercial disqualification runs on its own track. If you drive commercially, get attorney advice before assuming any restricted license covers your job.

Edge Cases: No Car, Motorcycles, Employer Cars, and Out-of-State Moves

I sold my car / I don’t own a car — does the IID requirement go away? No — but it pauses in a specific way. If, within 30 days of the DMV’s notification, you certify that you own no vehicle, have no access to a vehicle at your residence, no longer have access to the vehicle you were driving when arrested, and acknowledge that you may drive only an IID-equipped vehicle with a valid license, you are exempt from the installation requirements until you purchase or gain access to a vehicle (VC §23575.3(d)(2)). The restriction stays on your record, and the moment you get access to a car, the installation duty revives. Driving an unequipped car in violation of the exemption exposes you to the same penalties as any other violation. The requirement follows the driver and the license, not the car you happened to own at sentencing.

Can I ride a motorcycle with an IID restriction? No. The statute excludes motorcycles from the definition of “vehicle” for IID purposes until the state certifies a device that can be installed on a motorcycle — and it separately provides that a person under an IID restriction “shall not operate a motorcycle for the duration of the ignition interlock device restriction period” (VC §23575.3(o)(5)). Your motorcycle stays parked for the whole term, even if you have an IID in your car.

What about a work vehicle or a rental? Rentals and borrowed cars follow the general rule: every vehicle you operate must have a certified IID installed before you drive it while restricted — there is no “just this once” exception. Employer vehicles are the one general carve-out, and it is form-driven: if you hold an IID-restricted license, you may drive your employer’s vehicle in the scope of your employment without an IID if you complete the Notice to Employers Ignition Interlock Restriction (DL 923), give it to your employer, and keep a copy with you or in the vehicle (DMV IID page). Two limits: the DL 923 covers employment driving only, not personal errands in the work vehicle; and if you hold a no-vehicle exemption from mandatory installation, you do not qualify for the employer-vehicle exemption at all.

Drug-only DUI: no mandatory IID. The statewide IID program covers alcohol and alcohol-plus-drug DUIs. A drug-only DUI carries no mandatory IID term; repeat drug-only offenders may qualify for an IID-restricted license after serving at least one year of suspension or revocation (DMV page). If your case involved drugs only and a page tells you an IID is mandatory, it has the wrong program.

Can’t blow hard enough? There is a medical route. Drivers who cannot breathe with sufficient strength to activate an IID may seek a medical exemption through the DMV’s Mandatory Actions Unit (916) 657-6525; the DMV’s IID page cites form DL 4063 plus a provider note stating the limitation (provider license or certificate number and signature included). Attorney pages cite conflicting form numbers for this exemption, so confirm the current form on dmv.ca.gov before you file — and do not drive on a medical claim the DMV has not accepted.

Someone else drives your car: they blow too. The device cannot be switched off for other drivers — anyone who drives your IID-equipped car must provide the samples, and letting someone else blow for you is unlawful under VC §23247 (up to 6 months in county jail and/or a $5,000 fine, the same penalty band as tampering). Tell family members and friends before they borrow the car: the first beep will surprise them.

Selling the car mid-term: the restriction follows you, not the car. Tell your installer before you sell; the new vehicle needs its own installation and its own DL 920 filing with the DMV, and you may not drive the new car unequipped in the meantime. A sale, a trade-in, or a move to a new car never pauses or ends the term — only compliant months count.

Moving out of state does not erase the restriction. California’s IID restriction sits on your California driving record, and other states’ licensing agencies see it through interstate record-sharing. If you move, you will generally need to satisfy California’s IID term (or document its completion) before another state will issue you an unrestricted license. Do not assume a new state’s license wipes the California restriction — confirm the transfer treatment with both states’ DMVs before you move.

What if I fail a rolling retest? A failed retest is logged and reported through the installer’s data. A single failed sample does not automatically extend your term, but a pattern — failed retests, missed retests (which count as bypasses), missed services — is exactly what the installer must report, and the DMV acts on those reports. If you fail because of mouthwash, food, or medication, tell your installer and document it at the next service; do not try to “clear” the device yourself. And never let someone else blow for you: that is the textbook bypass, and it endangers both drivers’ licenses.

Removal: When the Device Comes Off

An honesty note first: neither the DMV’s IID page nor VC §23575.3 publishes a step-by-step removal procedure or a removal authorization form. The sequence below is the safe practical approach used by installers and attorneys — not an official checklist. If your installer or the DMV gives you a different removal instruction for your case, theirs wins.

Removal is the step drivers rush — and the step where rushing creates a new problem. The safe sequence is:

After removal, two things remain. First, the DUI conviction itself stays on your record under its own rules (it counts as a prior for 10 years for future DUI sentencing). Second, the SR-22 filing period runs on its own clock — generally 3 years after a first DUI — and does not end when the IID comes off. Removal ends the device, not the rest of the DUI consequences; see our reinstatement guide and SR-22 guide for the full checklist.

What Other IID Pages Get Wrong

We verified these errors while researching this page, so you can read the rest of the internet critically:

Where to verify everything on this page. The DMV’s IID program page and DUI pages on dmv.ca.gov, the Vehicle Code sections cited above on leginfo.legislature.ca.gov (VC §§23575.3, 23573, 23575, 13386, 13352, 13353.6), and AB 366’s chaptered text (Stats. 2025, Ch. 689). If any figure on this page ever conflicts with your sentencing order or the DMV’s notification letter, your order and letter win — they are the documents written for your case.

Related Guides

Last verified against dmv.ca.gov and leginfo.legislature.ca.gov: October 24, 2026. Statutes and DMV practice change — confirm current rules on dmv.ca.gov or with a lawyer before acting.