What’s the Difference Between DWI and DUI in Texas?

The difference between a DWI and a DUI in Texas comes down to age and the amount of alcohol involved. Driving While Intoxicated (DWI) is a criminal offense that applies to any driver whose blood alcohol concentration is 0.08 or higher, or whose mental or physical abilities are impaired by alcohol or drugs. Driving Under the Influence (DUI) is a separate, lesser offense that applies only to drivers under 21 who have any detectable amount of alcohol in their system. A first DWI is a jailable misdemeanor; a first DUI is closer to a traffic ticket.

How Texas Defines a DWI

Under the Texas Penal Code, you commit DWI if you operate a motor vehicle in a public place while intoxicated.¹ The state can prove intoxication two ways: a blood alcohol concentration (BAC) of 0.08 or higher, or the loss of normal use of mental or physical faculties due to alcohol, drugs, or any combination of substances.²

That second path matters. Even if your breath test reads below 0.08, you can still be charged with DWI if an officer and prosecutor can show your abilities were impaired. And DWI has no age minimum. A 19-year-old at 0.10 is charged with DWI, same as a 45-year-old at 0.10.

How Texas Defines a DUI

DUI lives in a different book entirely. It is defined in the Alcoholic Beverage Code and applies only to drivers under 21 who operate a motor vehicle in a public place with any detectable amount of alcohol in their system.³

Read that standard carefully: any detectable amount. There is no 0.08 threshold. There is no requirement that the minor act impaired, fail field sobriety tests, or drive erratically. A single beer that registers on a breath test is enough. This is Texas’s zero-tolerance rule for underage drinking and driving.

A Minor Can Be Charged With Either

This is the part most people get wrong. DWI and DUI are not mutually exclusive for drivers under 21. Which charge a prosecutor files depends on the facts.

A 20-year-old pulled over at a BAC of 0.05 would face a DUI, because any detectable alcohol triggers that offense but the number is below the DWI threshold. A 20-year-old at 0.09 can be charged with DWI, because they meet the 0.08 standard that applies to drivers of any age. A minor who is visibly impaired by drugs can also be charged with DWI regardless of their alcohol reading, since intoxication under the Penal Code includes impairment from controlled substances.²

The gap between the two charges is enormous. A DUI is a Class C misdemeanor with no jail time on a first offense. A DWI is a criminal offense that can put a minor behind bars. Prosecutors have discretion over which to file, and when the facts support DWI, they can and do use it.

What a DWI Conviction Costs

Texas DWI penalties escalate quickly with the circumstances and your prior record.

First offense: a Class B misdemeanor with a minimum of 72 hours in jail (up to 180 days) and a fine of up to $2,000.¹
First offense with an open container in the vehicle: still a Class B misdemeanor, but the jail minimum rises to six days.¹
First offense with a BAC of 0.15 or higher: elevated to a Class A misdemeanor, with up to one year in jail and a fine of up to $4,000.¹
Second offense: a Class A misdemeanor with a mandatory minimum of 30 days in jail, up to one year, and a fine of up to $4,000.⁴
Third offense: a third-degree felony punishable by two to ten years in prison and a fine of up to $10,000.⁴
DWI with a child passenger under 15: a state jail felony, meaning 180 days to two years in a state jail facility and a fine of up to $10,000, even on a first offense.⁵⁶
DWI in a school crossing zone: also a state jail felony with the same penalty range.¹

Those are the criminal penalties alone. License reinstatement fees, insurance premium increases, alcohol education programs, and ignition interlock costs push the real total far above the fine printed in the judgment.

What a DUI Conviction Costs a Minor

DUI penalties for drivers under 21 start mild and grow with repeat offenses.

First offense: a Class C misdemeanor with a fine of up to $500, 20 to 40 hours of alcohol-related community service, a mandatory alcohol awareness course, and a 60-day license suspension.³⁷
Second offense: still a Class C misdemeanor, but community service climbs to 40 to 60 hours and the license suspension stretches to 120 days.³⁷
Third or subsequent offense: the fine jumps to between $500 and $2,000, up to 180 days in jail becomes possible, and the license suspension reaches 180 days. A minor with two or more prior DUI convictions is also ineligible for deferred disposition or deferred adjudication.³

The community service hours must be tied to alcohol education or prevention rather than general volunteer work.³

License Suspension Before You Are Ever Convicted

Your license is at risk the moment you fail a breath or blood test, regardless of what happens with the criminal case. The Texas Department of Public Safety can suspend it through the Administrative License Revocation program. For an adult with no prior alcohol-related contacts in the past ten years, that suspension runs 90 days. With a prior alcohol-related contact, it stretches to one year.⁷

Minors have their own schedule under the same program: 60 days for a first offense, 120 days for a second, and 180 days for a third or later.⁷

A DWI conviction brings a separate court-imposed suspension on top. A first conviction carries 90 days to one year; a second or third under the enhanced-penalty provisions carries 180 days to two years.⁸

Refusing the Breath or Blood Test

Texas has an implied consent law. By driving on Texas roads, you have already consented to providing a breath or blood sample if you are arrested for DWI or minor DUI.⁹ You can still refuse, but the refusal is its own penalty.

A first refusal suspends your license automatically for 180 days. If your record shows a prior alcohol-related or drug-related enforcement contact within the past ten years, the suspension doubles to two years.¹⁰ Compare that to the 90 days you would face for failing a test with no prior contacts. Refusing also does not guarantee you avoid the criminal charge, since officers can seek a warrant to draw blood.

The Quick Comparison

Who it applies to: DWI covers any driver. DUI covers only drivers under 21.
Standard of proof: DWI requires a BAC of 0.08 or higher, or lost normal use of mental or physical abilities. DUI requires only any detectable amount of alcohol.²³
Where the law lives: DWI is in the Penal Code. DUI is in the Alcoholic Beverage Code.
First-offense classification: DWI starts as a Class B misdemeanor with mandatory jail time. DUI starts as a Class C misdemeanor with no jail time.¹¹¹
Jail exposure: a first DWI carries a 72-hour jail minimum. A first DUI carries none; only a third-offense DUI opens the door to confinement.
Drugs: DWI covers impairment from controlled substances and other drugs. DUI covers alcohol only.

The detail that trips up most families is the overlap for drivers under 21. A 17-year-old who had one drink faces a DUI. That same 17-year-old after several drinks can face a DWI with the full adult penalty range.

1
State of Texas. Texas Penal Code 49.04 – Driving While Intoxicated
2
State of Texas. Texas Penal Code 49.01 – Definitions
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State of Texas. Texas Alcoholic Beverage Code 106.041 – Driving or Operating Watercraft Under the Influence of Alcohol by Minor
4
State of Texas. Texas Penal Code 49.09 – Enhanced Offenses and Penalties
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State of Texas. Texas Penal Code 49.045 – Driving While Intoxicated With Child Passenger
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State of Texas. Texas Penal Code 12.35 – State Jail Felony Punishment
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Texas Public Law. Texas Transportation Code 524.022 – Period of Suspension
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Texas Public Law. Texas Transportation Code 521.344 – Suspension for Offenses Involving Intoxication
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State of Texas. Texas Transportation Code 724.011 – Consent to Taking of Specimen
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State of Texas. Texas Transportation Code 724.035 – Suspension or Denial of License on Refusal
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State of Texas. Texas Penal Code 12.23 – Class C Misdemeanor