Idaho DUI Penalties: Jail, Fines, License Suspension, and Interlock

Idaho DUI penalties depend on the exact charge, the person’s qualifying history, the test result alleged, whether anyone was seriously injured, and the sentencing court’s order. A first ordinary DUI, a second offense, an excessive DUI, and an aggravated DUI do not carry the same minimums or maximums.

The ranges below come from current Idaho statutes. They are not a prediction of what will happen in a particular case. A charge is not a conviction, and a statutory maximum is not an “average sentence.”

A DUI arrest can also start a separate driver’s-license proceeding before the criminal case ends. If an officer served a failed-test suspension notice, the Idaho Transportation Department must receive a hearing request within seven calendar days after service. See the firm’s Idaho administrative license suspension guide.

Idaho DUI penalties at a glance

The first-offense license entry in the table describes an ordinary noncommercial DUI under Idaho Code sections 18-8004(1)(a) and 18-8005(1), whether the theory is impairment or an alcohol concentration of 0.08 or more. Commercial-motor-vehicle cases under subsections (1)(b) and (1)(c) use additional license provisions and can affect both Class D and commercial privileges. See the firm’s guides to Idaho drug DUI and CDL DUI consequences.

Idaho’s repeat-offense rules contain detailed definitions, lookback calculations, and treatment of prior or foreign cases. A label on a driving record does not by itself resolve whether a prior legally enhances the new charge. The dedicated second-offense, excessive-DUI, and felony-DUI guides explain those rules without duplicating them here.

How the charge changes the penalty

• Ordinary first DUI: Idaho Code section 18-8005 authorizes up to six months in jail but does not set a mandatory minimum jail term for a first ordinary adult DUI. The written judgment can still include jail within the range, probation, evaluation or treatment, a fine, license restrictions, interlock, and other lawful conditions.
• Repeat DUI: A qualifying prior within the statutory period adds mandatory custody and can change a later charge from a misdemeanor to a felony. The identity, date, statute, judgment, and legal effect of each alleged prior should be checked; the detailed second-offense and felony-DUI guides explain those enhancement paths.
• Excessive DUI: Section 18-8004C applies when the state proves the underlying DUI and a police-requested blood, breath, or urine analysis shows 0.20 or more. Its special felony provision requires a qualifying prior 0.20-or-higher violation within five years. See the excessive-DUI guide.
• Aggravated DUI: This is different from excessive DUI. Section 18-8006 concerns causing great bodily harm, permanent disability, or permanent disfigurement to another person while committing a covered DUI violation. Injury and causation are addressed in the aggravated-DUI guide.

Underage DUI penalties in Idaho

Idaho has a separate alcohol-concentration offense for a driver under 21 with a result of at least 0.02 but less than 0.08. For a first violation, Idaho Code section 18-8004A makes the offense a misdemeanor, authorizes a fine of up to $1,000, requires an alcohol evaluation, and imposes a one-year court suspension. The first 90 days are absolute; restricted privileges may be requested for the remainder.

Repeat under-21 violations can add mandatory jail, minimum fines, longer absolute suspension, and ignition-interlock-restricted driving. A driver under 21 with a result of 0.08 or more—or whose ability to drive is impaired by alcohol, drugs, or another intoxicating substance—can face the ordinary DUI provisions rather than only the 0.02 law. Age and juvenile-court rules can create additional issues. Read the Idaho underage-DUI guide for the distinct thresholds and repeat-offense rules.

A DUI arrest can create more than one license case

The court suspension imposed after a conviction is only one possible license action. The same incident can also produce a separate failed-test suspension through ITD or a court refusal suspension:

• Failed evidentiary test: A first administrative license suspension is 90 days, with the first 30 days absolute. A second failed test within five years produces a one-year suspension with no ordinary restricted permit. The hearing deadline is seven calendar days after service of the notice.
• Alleged test refusal: A first refusal can produce a one-year suspension with no ordinary restricted permit; a second refusal within 10 years can produce a two-year suspension. The request for a court hearing must be made within seven days from the refusal. See the Idaho implied-consent and test-refusal guide.
• Criminal conviction: The sentencing court imposes the suspension required by the conviction statute. Its start date, absolute period, and any possible restricted privileges depend on the charge.

These proceedings are separate. A dismissal or acquittal in the criminal case does not automatically erase an ALS that was not timely challenged or was sustained, and the end of a suspension period does not automatically make the license valid.

Before driving, verify the status directly with ITD. Reinstatement may require payment of the applicable fee, proof of financial responsibility, satisfaction of an interlock restriction, and clearance of every active withdrawal. ITD currently states that a person convicted of DUI must maintain an SR-22 filing for three years beginning at the conclusion of the suspension. The firm’s Idaho SR-22 and license-reinstatement guide explains those steps.

Ignition interlock is a separate operating restriction

An ignition interlock is not simply another suspension. It is a restriction that allows operation only of a properly equipped vehicle when the applicable statute or order requires it. Idaho law can require interlock-restricted driving after an ordinary adult DUI, a repeat DUI, an excessive DUI, certain repeat underage offenses, a failed-test administrative suspension, or a test-refusal suspension.

Idaho amended its interlock statute effective July 1, 2026. For a one-year restriction governed by Idaho Code section 18-8008, the period ends one year from the date the vendor provides proof of installation to ITD. Overlapping court and administrative requirements can still create different controlling dates. Use the written order and current driver record, and do not remove a device based only on a calendar estimate. See the Idaho ignition-interlock guide.

Probation, evaluation, and treatment

Probation is not a single standard DUI penalty with a fixed length or identical conditions. A court may suspend part of an authorized sentence and impose lawful conditions during probation. Depending on the case and order, conditions can involve reporting, alcohol or drug testing, abstinence, treatment, monitoring, travel restrictions, payment obligations, or no new violations.

A probation violation does not automatically establish every allegation against the person, but it can lead to a violation proceeding and possible imposition of suspended consequences. The judgment and probation order should be read word for word.

Idaho Code section 18-8005 generally requires a person who pleads guilty to or is found guilty of ordinary, excessive, or aggravated DUI to obtain an approved alcohol evaluation before sentencing. The statute gives a court limited waiver authority in specified first-offense circumstances. When an evaluation recommends treatment, the court generally must order the recommended program or a comparable alternative unless it makes findings that treatment would be inappropriate or undesirable.

Fines are not the total financial cost

The amounts in the table are statutory maximum fines, not estimates of the total cost and not predictions of the fine a judge will impose. Separate obligations may include court assessments, restitution, evaluation and treatment, probation or monitoring, license-reinstatement fees, ignition-interlock service, SR-22-related insurance costs, transportation, missed work, and legal expenses.

Aggravated DUI expressly requires restitution. Restitution can also arise under generally applicable law when an offense causes compensable economic loss. The amount and recipient depend on the case and the court’s order. For a category-by-category explanation, see what an Idaho DUI can cost.

Collateral consequences can outlast the sentence

Consequences outside the jail-and-fine table depend heavily on the person’s circumstances. They can include:

• higher insurance costs and the need to maintain an SR-22 filing;
• loss of transportation or limits on work, school, medical, and family travel;
• employment consequences, particularly for driving-dependent or safety-sensitive work;
• professional-license, military, security-clearance, or school-discipline reporting issues;
• commercial-driver disqualification, for which no restricted commercial driving privilege is available;
• civil claims and restitution when a crash causes injury or property loss;
• use of the conviction or guilty plea in a future DUI enhancement; and
• immigration consequences that should be reviewed with qualified immigration counsel before a noncitizen resolves the criminal case.

Not every item applies to every person. A withheld judgment or later dismissal also should not be assumed to erase the historical plea or every licensing, employment, or enhancement consequence.

Sentencing ranges matter only if there is a guilty plea or finding of guilt. The Ada County DUI court-process guide explains arraignment, discovery, motions, plea discussions, trial, and sentencing. The separate Idaho DUI defense guide explains how the stop, driving allegation, statements, field observations, and chemical-test evidence may be reviewed.

Frequently asked questions

Is jail mandatory for a first DUI in Idaho?

Not for an ordinary first adult DUI under Idaho Code section 18-8005(1); that statute authorizes up to six months but does not set a mandatory minimum jail term. A first excessive DUI, aggravated DUI, and some repeat or differently charged offenses carry mandatory custody provisions.

Can I get a work permit during a DUI suspension?

It depends on the particular suspension. After the 30-day absolute period for a first ordinary alcohol DUI, the sentencing court may grant restricted privileges during the remaining suspension if the statutory showing is made. No ordinary permit is available during the one-year absolute suspension for a second DUI. An ALS permit is a separate ITD process. Narrow problem-solving-court provisions may apply in qualifying cases, but they are not a general hardship exception.

Can one arrest create two license suspensions?

Yes. A failed test can create an administrative suspension, while a later conviction can create a separate court suspension. A refusal allegation uses another court process. Each notice, deadline, order, fee, and reinstatement requirement must be checked.

Does paying a reinstatement fee make the license valid?

Not necessarily. The time period, SR-22 filing, ignition-interlock requirement, permit terms, and every other active withdrawal must also be satisfied. Confirm the current status with ITD before driving.

Review the charge and both license tracks

A useful case review starts with the citation or complaint, every page of the license notice, the alleged test result, the person’s complete prior record, and the next court date. Contact Attorneys of Idaho or call 208-314-8888 to discuss an Idaho DUI charge and any separate license deadline.

This page provides general information, not legal advice for a particular case. Statutes, agency requirements, and court procedures can change.