DUI limits, penalties and test refusal

Key points

1. You are DUI at a BAC of .02 or more if under 21, .04 or more in a commercial vehicle, and .08 or more at 21 or older.

   Source: Handbook p. 131

   “your blood-alcohol concentration (BAC) is .02 or more if you are under 21 years of age, .04 or more if you are operating a commercial vehicle, and .08 or more if you are 21 or older.”
   Idaho Driver's Handbook, Handbook p. 131

2. A BAC of .20 or more carries even stiffer penalties.

   Source: Handbook p. 131

   “An alcohol concentration of .20 or more carries even stiffer penalties.”
   Idaho Driver's Handbook, Handbook p. 131

3. A first DUI conviction means up to 6 months in jail, up to a $1,000 fine, and a 90 to 180 day suspension.

   Source: Handbook p. 132

   “For a first conviction: Up to six months in jail; up to a $1,000 fine; and mandatory driver's license suspension of at least 90 days and up to 180 days”
   Idaho Driver's Handbook, Handbook p. 132

4. A second DUI within 10 years means at least 10 days in jail, up to a $2,000 fine and a 1 year suspension.

   Source: Handbook p. 132

   “For a second conviction within 10 years: Mandatory jail sentence from 10 days to one year (30 days if you are under 21); up to a $2,000 fine; and a mandatory driver's license suspension of one year”
   Idaho Driver's Handbook, Handbook p. 132

5. Refusing a requested test brings a license suspension and a $250.00 civil penalty.

   Source: Handbook p. 126

   “you are subject to a driver's license suspension and a civil penalty of $250.00”
   Idaho Driver's Handbook, Handbook p. 126

6. A first refusal means a 1 year suspension with no driving privileges.

   Source: Handbook p. 126

   “your license will be suspended for one year with absolutely no driving privileges of any kind if it is your first offense.”
   Idaho Driver's Handbook, Handbook p. 126

7. A second refusal within 10 years means a two year absolute suspension.

   Source: Handbook p. 127

   “A second refusal within 10 years will result in a two-year absolute suspension.”
   Idaho Driver's Handbook, Handbook p. 127

8. After a serious offense such as DUI, you must show proof of financial responsibility for 3 years.

   Source: Handbook p. 128

   “you must also provide proof of financial responsibility for three years.”
   Idaho Driver's Handbook, Handbook p. 128

Numbers to know

3 questions from the Idaho practice test

1. 1. What happens to a DUI conviction in Idaho when the driver's BAC is 0.20 percent or higher?

   1. The conviction is reduced to a traffic warning
   2. Enhanced penalties apply beyond a standard DUI
   3. Only the vehicle registration is affected
   4. The driver receives no additional consequence
   Show answer

   Enhanced penalties apply beyond a standard DUI. Idaho treats a BAC of 0.20 percent or higher as a threshold for enhanced DUI penalties. That means the consequence is more serious than the ordinary DUI baseline, rather than a warning or a registration-only issue. The no-additional-consequence choice ignores the heightened alcohol concentration. Do not use a legal threshold as a target: any impaired driving can injure people, and the safest decision is to arrange a sober ride before drinking begins.

2. 2. What follows a second refusal of an evidentiary test within 10 years in Idaho?

   1. A 90 day suspension
   2. A two year absolute suspension
   3. A $250 fine only
   4. No additional penalty
   Show answer

   A two year absolute suspension. A first refusal brings a one year suspension with no driving privileges and a $250 civil penalty, and a second refusal within 10 years results in a two year absolute suspension, in addition to any court penalty for a DUI conviction. Refusing does not keep the evidence out of court, and it costs more license time than failing the test.

3. 3. How long must an Idaho driver keep an SR-22 on file after a suspension for a serious offense?

   1. Three years
   2. One year
   3. 30 days
   4. Ten years
   Show answer

   Three years. If your license was suspended for certain serious offenses such as reckless driving or driving under the influence, you must provide proof of financial responsibility for three years, in the form of an SR-22 certified statement of liability coverage from your insurer. The SR-22 is separate from ordinary proof of insurance and is not accepted as insurance proof for a skills test.

Source: the Idaho Driver's Handbook, What Affects Your Driving Privilege and Record. This lesson is a plain English summary, not the law itself; where it differs, the manual and the statute govern. Last checked 2026-09-27.