DWI vs. DUI: Understanding the Difference

by Ann deBruyn

DUI and DWI both refer to driving while impaired, typically by alcohol or drugs. DUI stands for “driving under the influence” while DWI means “driving while intoxicated” or “driving while impaired.”

Here's what to know about how DUI and DWI convictions happen, how terms may vary by state, plus the impact a conviction may have on your driving record.

DWI vs. DUI: Definitions and terms can vary by state

Check your state’s laws to know how a DWI or DUI is defined. For example, in Texas, the terms DUI and DWI are often used interchangeably, while Maryland uses the terms to describe separate offenses. In states where DUI and DWI are defined differently, one usually carries a more serious penalty than the other.

Your state may also use different terms entirely, such as:

  • OUI, or operating under the influence.

  • OWI, or operating while intoxicated.

  • DWAI, or driving while ability impaired.

How DUI and DWI convictions happen

Driving with a high blood alcohol content, or BAC, is a common way to be charged with a DUI or DWI. BAC measures how much alcohol is in a person’s system, and in most states, driving with levels of 0.08% or higher is illegal, regardless of whether the driver feels impaired.

But DUIs and DWIs are not only related to alcohol. Depending on the state, a person can be charged with a DUI or DWI for any of the following reasons:

  • Being impaired due to drugs, including medications prescribed by a doctor.

  • Being too tired to safely operate a vehicle.

  • Sitting in a vehicle while under the influence, even if the vehicle is not in motion. In this circumstance, an officer may consider other factors before making an arrest, such as whether the engine is running and whether the impaired person is in the driver’s seat.

The impact of a DUI or DWI

You’ll likely be deemed a high-risk driver and may need to shop around for new coverage if your insurer will no longer cover you. You may also be required by your state to have your auto insurer file an SR-22 form on your behalf to prove you’ve purchased at least the minimum required car insurance in your state. In Florida or Virginia, you may need an FR-44 form to prove you’ve bought the higher amounts of coverage those states require after certain convictions.

If you’ve been dropped by your insurer for a DUI or DWI conviction and need to shop around for new coverage, check out NerdWallet’s list of the best high-risk car insurance companies .