What Is the Difference Between DUI and DWI?

Driving Under the Influence and Impaired Driving

DUI Arizona
Police Make a DUI Stop. Joe Raedle / Getty Images

DUI is an acronym for driving under the influence. DWI stands for driving while intoxicated, or in some cases, driving while impaired. The terms can have different meanings or they can refer to the same offense, depending on the state.

In any case, they mean that a driver is being charged with a serious offense that risked the health and safety of himself and others. They can apply not only to alcohol or recreational drugs but also to driving when your prescription drugs impair your abilities.

Learn more about impaired driving charges and how they can affect your life.

State Definitions Differ for DUI and DWI

Depending on state law, the two terms are both used to describe impaired or drunken driving. Some state laws refer to the offense of drunken driving as DUI and others call it DWI.

It gets tricky when states use both terms, applying one to alcohol and the other to impairment by drugs or an unknown substance. The meaning can flip-flop from state to state. In some states, DWI refers to driving while intoxicated of alcohol with a blood alcohol content (BAC) over the legal limit, while DUI is used when the driver is charged with being under the influence of alcohol or drugs.

In other states where both terms are used, DWI means driving while impaired (by drugs, alcohol or some unknown substance), while DUI means driving under the influence of alcohol. You have to check the definitions state by state.


There are other acronyms for drunk driving. OUI, or operating under the influence, is used in only three states: Maine, Massachusetts and Rhode Island. The "operating" distinction encompasses more than just driving the vehicle. Even if the vehicle is stopped and not running, someone can be charged with operating under the influence.

OWI is an acronym for operating while intoxicated which is used in some jurisdictions.

Driving While Impaired

Any of these charges mean the arresting officer has reason to believe the driver is too impaired to continue to drive. In some jurisdictions, drivers can be charged with impaired driving (or driving under the influence) even if they do not meet the blood alcohol concentration levels for legal intoxication.

For example, if you fail a field sobriety test or otherwise show signs of impairment, you can be charged with driving while impaired even if your blood-alcohol concentration is under the legal limit of 0.08.

Drugged Driving Is Impaired Driving

If you appear to be impaired to the arresting officer, but your breathalyzer test shows that you are not under the influence of alcohol, the officer can call a Drug Recognition Expert to the scene to determine if you are under the influence drugs.

If the DRE officer's multi-step evaluation process determines that you are indeed under the influence of drugs, you can be charged with DWI or DUI, depending on what the state you are in calls the offense of drugged driving. You have to be responsible when taking prescription or nonprescription medications that can impair your driving ability, and you are at risk for these charges even when not drinking alcohol.

After an Impaired Driving Arrest

No matter what the offense is called in your jurisdiction—DUI or DWI—if you are arrested for drunk driving, driving under the influence, or driving while intoxicated, you will be facing serious consequences.

If you are convicted or plead guilty of drunk driving, you will probably lose your driver's license and pay fines and court fees; if it's a second offense, you may spend some time in jail. You will probably be placed on probation and perform community service. To get your driver's license back, you will probably have to attend defensive driving classes.

In most states, you will also probably undergo an evaluation of your drinking patterns and based on the results of that evaluation, you may have to take part in an alcohol treatment program.

That program could range from attending a few Alcoholics Anonymous or other support-group meetings to entering a residential treatment facility.

Ongoing Expense and Effects of a DUI or DWI Conviction

When you get your driver's license back, you will find that you will also need SR-22 insurance, which could double or triple your premiums, depending on the laws in your state. You will probably have to pay the higher premiums for three years.

Also, depending on the state in which you reside, you may have to have an ignition interlock device installed on your vehicle, which will require you to pay for the device, the installation, and a monthly monitoring fee.

The bottom line is getting arrested for driving under the influence is a time-consuming and very expensive ordeal, but it is 100 percent avoidable. Just don't get behind the wheel while you are drinking.

A Word From Verywell

You can protect your health and safety as well as that of others by never driving after drinking any amount of alcohol. Your abilities will be impaired even if your blood alcohol content is below the legal limit. If you are taking any prescription or non-prescribed drugs that carry a warning of impaired driving, it's best not to get behind the wheel. The laws are in place to keep you and everyone else healthy and safe.


Drunk Driving. NHTSA. https://www.nhtsa.gov/risky-driving/drunk-driving. Published March 30, 2017.