How long does alcohol stay on your breath?

Alcohol can remain on your breath for up to 12 to 24 hours after consuming your last drink.¹ Keep in mind, however, that everyone’s body is different, and the absorption of alcohol and its detection will vary by body type.

Note that alcohol on your breath, on its own, does not necessarily mean that you will get arrested for DUI. Police must have evidence that you were driving while intoxicated before they can lawfully arrest you for the offense.

While the smell of alcohol is evidence of alcohol consumption, police usually need more, like:

• failed breath test results,
• failed blood test results,
• failed field sobriety tests, or
• open containers of alcohol in your car.

If you were arrested for DUI, please contact a skilled DUI attorney now for assistance.

1. Does alcohol remain on your breath for a long time?

The presence of alcohol can stay on your breath for up to 12 to 24 hours after having your last consumption.²

A result is that police could suspect you of drunk driving long after you stopped drinking.

Consider, for example, the scenario where you drink excessively one night and end up going to bed at 2 a.m. You wake up at a little after noon and drive for a cup of coffee. A police officer stops you for speeding and smells alcohol on your breath. The odor may lead the officer to question you about driving while under the influence.

Note that some acts can help reduce the smell of alcohol on your breath. Examples include:

• using mouthwash, and
• brushing your teeth.

2. Does the smell of alcohol mean a failed breathalyzer test?

Not necessarily, no. A breath test attempts to measure a person’s blood alcohol concentration or blood alcohol content (BAC).

BAC is the measure of the amount of alcohol in your bloodstream. BAC is expressed as a percentage – for instance .08% (the legal limit in most states).³

Breath tests work by:

• measuring alcohol in the deep lung tissue (alveoli), and then
• using a partition ratio to estimate the blood alcohol level based on the breath alcohol level.

If your breath smells like alcohol, this does not necessarily mean that there is a sufficient amount of alcohol in your deep lung tissue to register a BAC of .08% or higher.

Note that alcohol can remain in your blood for up to six hours after having an alcoholic beverage.⁴      

Since alcohol can remain on your breath for a longer period of time, it is quite possible to have odor on your breath while much if not all of the alcohol in your system has been expended.

3. Will you get arrested for DUI if you have alcohol on your breath?

Not necessarily, no. Police have to have evidence that you were driving while intoxicated before they can arrest you for DUI.

Granted, the smell of alcohol on your breath is possible evidence of alcohol consumption. However, on its own, it is usually not enough evidence to support a driving while drunk arrest.

But note that the odor of alcohol may suggest alcohol use, and it may lead a police officer to begin investigating you for a DUI offense.

4. What does the breakdown of alcohol involve?

While alcohol passes through your digestive tract, it does not undergo significant digestion in this tract like food does.

When it enters your digestive tract, a large amount of alcohol is absorbed into your bloodstream through the tissue that lines your stomach and small intestine.

Once in your blood, the alcohol eventually reaches your liver which processes alcohol, or is the organ primarily responsible for alcohol metabolism. The metabolism process relies on specific enzymes within your body (one example is alcohol dehydrogenase (ADH)).⁵

Note that the absorption of alcohol in your system can increase if you:

• drink on an empty stomach, or
• engage in binge drinking.

Note, too, that some drinkers can reduce the absorption of alcohol in their system (and thereby help reduce the effects of alcohol) by:

• eating food,
• drinking water, and
• consuming drinks slowly.

5. Can a criminal defense attorney help in DUI cases?

Yes. You should consult with a skilled defense lawyer or DUI lawyer if you are arrested for DUI.

DUI is a serious offense that can result in such penalties as:

• jail time,
• suspension of your driver’s license, and
• substantial fines.

A DUI attorney can help you raise a legal defense so as to avoid these penalties or minimize them.

Note that most lawyers and law firms/law offices provide consultations. This means you can get legal advice in your DUI case at no cost.

Additional reading

For more in-depth information, refer to these scholarly articles:

• Reflections on Variability in the Blood–Breath Ratio of Ethanol and its Importance When Evidential Breath-Alcohol Instruments are Used in Law Enforcement – Forensic Sciences Research.
• Alcohol Breath Testing: Is There Reasonable Doubt? – Syracuse Journal of Science and Technology.
• Breath analysis in law enforcement – Breathborne Biomarkers and the Human Volatilome (Second Edition) article about how breath machine results factor into police’s formulation of probable cause.
• Elimination rates of breath alcohol – Forensic Science International article about how quickly breath alcohol dissipates.
• To Breathe, or Not to Breathe: Passive Alcohol Sensors and the Fourth Amendment – San Diego Law Review.
• The Analytical Limitations of Modern Breath Alcohol Testing: A Call for Reform to Per Se Mandatory Sentencing Enhancement Schemes – Gonzaga Law Review.

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