What is the legal BAC limit for drivers in California?

What is the Legal BAC Limit for Drivers in California?

The legal blood alcohol concentration (BAC) limit for drivers in California depends on several factors, including the driver’s age and whether they are operating a commercial vehicle.

The Standard Limit for Adult Drivers

For most adult drivers over the age of 21 operating non-commercial vehicles in California, the legal BAC limit is 0.08%. This means it is illegal to drive with a blood alcohol concentration of 0.08% or higher.Driving with a BAC at or above 0.08% is a violation of [California Vehicle Code 23152(b)]


. A first-time conviction carries penalties including:

  • Fines of $390-$1000
  • Up to 6 months in jail
  • A 6-month license suspension

Penalties increase for repeat offenses within 10 years.

Lower Limits for Some Drivers

However, California law imposes stricter BAC limits on certain drivers:

Underage Drivers

For drivers under 21 years old, the legal limit is much lower, at 0.01% BAC. This “zero tolerance” policy is codified in [California Vehicle Code 23136]


.Driving with a BAC of 0.01% or higher will result in a 1-year license suspension. Additional penalties may include fines, alcohol education classes, and possible vehicle impoundment.

Commercial Drivers

The BAC limit for commercial drivers is 0.04%, per [California Vehicle Code 23152(d)]


.Commercial drivers face fines of $390-$1000, jail time up to 12 months, license suspension for at least 1 year, and disqualification from operating a commercial vehicle for 1 year.

Rideshare and Taxi Drivers

For taxi drivers, limo drivers, Uber and Lyft drivers, and other “drivers for hire,” the BAC limit is 0.04% when transporting passengers, according to [California Vehicle Code 23152(e)]


.Penalties include fines of $390-$1000, up to 6 months in jail, and license suspension from 6-10 months.

DUI Conviction Penalties

Being convicted of driving under the influence (DUI) in California has severe consequences beyond just fines and license suspensions.Additional penalties for a first DUI conviction can include:

  • Up to 6 months in jail
  • Fines up to $1000 plus penalty assessments
  • Completion of a DUI program
  • An SR-22 requirement for 3 years
  • Possible vehicle impoundment

Penalties escalate sharply for second and subsequent offenses within 10 years.A second DUI conviction can result in fines up to $1000, 10 days to 1 year in jail, an 18-month license suspension, and more.A third DUI conviction within 10 years can bring fines up to $1000, 120 days to 1 year in jail, a 3-year license revocation, and an ignition interlock device requirement.Fourth and subsequent offenses are prosecuted as felonies in California, with even harsher punishments.

DUI Investigations

When police pull over a driver they suspect of DUI, they usually conduct a series of [field sobriety tests]


 to assess impairment.They may also ask the driver to take a preliminary alcohol screening (PAS) breath test. PAS tests are voluntary, and drivers can refuse.However, refusing a PAS test or performing poorly on field sobriety tests gives police reasonable cause to make a DUI arrest.After arrest, police can compel a breath or blood test to measure the driver’s BAC. Drivers who refuse these chemical tests face increased penalties.

BAC Testing Methods

There are a few different methods police use to test BAC levels:Breath TestingBreath testing using a handheld preliminary device or evidentiary breathalyzer machine at the police station. It’s the most common DUI testing method.Blood TestingA blood sample can be collected at the police station or hospital to directly measure blood alcohol content.Urine TestingUrine samples may be used if other testing is unavailable, but urine tests are less reliable for determining impairment.Breath and blood testing are generally considered the most accurate methods for measuring BAC. Proper testing procedures must be followed for the results to be admissible in a DUI prosecution.

Factors Affecting BAC Levels

Many variables influence an individual’s blood alcohol concentration. Factors like body weight, gender, metabolism, and stomach contents all impact how quickly alcohol is absorbed and processed.However, the major factors affecting BAC levels are:

  • Number of Drinks – The more alcohol consumed, the higher BAC rises
  • Strength of Drinks – Beverages with higher alcohol content increase BAC faster
  • Time Spent Drinking – BAC continues to climb as long as alcohol is still being consumed
  • Time Passed – It takes roughly 1 hour for the liver to process 0.015% BAC

For most people, BAC will exceed 0.08% after consuming 4-5 standard drinks in a short period of time.But there are no hard rules, since alcohol affects each person differently. Even one or two drinks can put some individuals over the legal limit.

DUI Without Exceeding the Legal Limit

Importantly, drivers can still be arrested and convicted for DUI even if their BAC is under 0.08%.California law prohibits driving “under the influence” of alcohol or drugs. This is based on the driver’s impairment, not just their BAC number.So exhibiting slurred speech, lack of balance, delayed reactions, or other signs of impairment can establish a DUI charge.In these cases, the prosecution relies on the arresting officer’s observations rather than chemical test results. Drivers should never assume they are “safe” to drive after drinking just because their BAC is technically legal.

Consequences of Refusing BAC Testing

Refusing to submit to chemical BAC testing after being arrested for DUI leads to serious consequences in California.Drivers who refuse breath or blood tests face:

  • A 1-year license suspension from the DMV
  • Longer DUI program requirements
  • Enhanced penalties if later convicted of DUI

However, refusing testing might benefit some drivers with extremely high BAC levels that would drastically increase penalties.An experienced DUI defense attorney can advise whether refusing testing is a good strategy in individual cases.

The Bottom Line on California’s BAC Limits

The legal BAC limit for most adult drivers over 21 in California is 0.08%, but lower limits apply to underage, commercial, and rideshare drivers.Driving impaired at any BAC level is illegal. The penalties for DUI increase sharply for repeat offenses within 10 years.Drivers should be aware of their limits, use good judgment, and never operate a vehicle after drinking too much. Knowing California’s BAC laws and limits is vital for staying safe and avoiding severe legal punishments.


[California DUI Laws Overview][California Driver Handbook – Alcohol and Drugs][BAC Calculator]


https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?sectionNum=23152.&lawCode=VEH[2]: https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?sectionNum=23136.&lawCode=VEH


https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?sectionNum=23152.&lawCode=VEH[4]: https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=VEH&sectionNum=23152.