Texas Legal Limit: What Blood Alcohol Level Is Classified as Driving While Intoxicated?

Short answer: In Texas, a driver is legally intoxicated at a blood alcohol concentration (BAC) of 0.08% or higher. A result of 0.15% or more triggers a “high‑BAC” enhancement with tougher penalties; commercial drivers are held to 0.04% while operating a commercial vehicle, and drivers under 21 can be cited for any detectable alcohol. If you’re searching for the Texas driving while intoxicated blood alcohol level because of a recent stop in Houston or Harris County, these numbers are what Texas uses to classify “driving while intoxicated.”

Texas driving while intoxicated blood alcohol level: the numbers you need to know

Texas law defines intoxication in two ways: (1) loss of normal use of mental or physical faculties because of alcohol or drugs, and (2) having an alcohol concentration of 0.08 or more. That second definition is the “per se” rule—meaning the number alone can support a DWI charge. A test at or above 0.15% is treated as a high‑BAC case with enhanced penalties. Commercial drivers face a 0.04% limit while operating a CMV, and anyone under 21 can be cited for any detectable amount of alcohol. For the full statutory language, see the Texas Penal Code chapter defining intoxication and BAC rules.

If you want a quick refresher on these limits and related exceptions, this overview of what counts as intoxication and BAC limits in Texas summarizes where the 0.08, 0.15+, commercial, and under‑21 standards come from and how they appear in real cases.

Why this matters to you: if your breath or blood test reads 0.08 or higher, the officer and prosecutor will likely focus on the number. If it’s 0.15 or higher, the case is handled more aggressively and may involve ignition interlock and other conditions during your case. If your job requires a clean driving record or a CDL, your livelihood may be directly affected by the Houston DWI BAC threshold that applies to your role.

How Texas measures BAC (and what the numbers really mean)

Police measure BAC with either a breath test (usually at the station) or a blood test. Breath tests estimate alcohol concentration using a machine that must be maintained, calibrated, and operated under specific procedures. Blood tests measure alcohol in a sample sent to a lab. Both methods have rules, margins of error, and human steps where things can go wrong.

For someone worried about work and family: your BAC number is not the whole story. How the number was obtained matters. A result just above 0.08 can be influenced by machine error, medical conditions (like GERD), mouth alcohol, improper observation periods, or timing issues (rising BAC between driving and testing). A 0.15 or higher result is serious, but accuracy and procedure still matter—especially with blood draws, chain of custody, and lab analysis.

Quick definitions you’ll hear:

• Per se BAC (0.08+): Texas’s “bright line” for DWI. A test at or above 0.08 can support a DWI without proving actual impairment.
• High BAC (0.15+): Same offense, but enhanced to a higher misdemeanor level with tougher potential penalties and bond conditions.
• Commercial limit (0.04): Applies only while operating a commercial motor vehicle. If you hold a CDL, even an off‑duty DWI can threaten your CDL qualifications later.
• Minor (under 21): “Any detectable amount” of alcohol can support a citation; the standard is different from adult DWI.

What changes at 0.15%? (The high‑BAC enhancement explained)

Texas treats a BAC of 0.15% or higher as a more serious form of a first‑offense DWI. It’s still a misdemeanor, but the classification and potential consequences go up. Courts in Houston and surrounding counties often impose ignition interlock while the case is pending, and they may limit travel, alcohol use, and even work‑related driving.

If you’re dealing with a high BAC and a busy work schedule, here’s the bottom line: the court and prosecutors see 0.15+ as a bigger public‑safety risk. That can mean stricter bond conditions, closer supervision, and a greater chance of mandatory interlock. For an overview of the common ranges for jail exposure, fines, and license consequences by BAC bracket, see this explainer on penalties and possible consequences for different BAC levels. A practical companion read on how BAC numbers affect charges and penalties in Texas can also help you translate the statute into real‑world outcomes.

Typical ranges you’ll hear about for a first DWI in Texas (not exhaustive):

• Class B misdemeanor (0.08–0.149): Up to 180 days in county jail and up to a $2,000 fine, plus court costs and state‑imposed fines. Courts may allow probation in many cases.
• Class A misdemeanor (0.15+): Up to 1 year in county jail and up to a $4,000 fine, with potential interlock requirements and stricter probation terms if granted.
• State traffic fines: The law also adds state fines that can range from $3,000 to $6,000 depending on your BAC and prior history, separate from regular fines and fees.

These are maximums and general ranges, not predictions for your case. Outcomes vary based on the facts, history, and how the evidence holds up.

License impact and the 15‑day ALR clock (act quickly to protect driving)

After a DWI arrest in Texas, the license process runs on a separate track called Administrative License Revocation (ALR). If you provided a specimen at or above 0.08, or refused testing, you usually receive a notice that your license will be suspended. You have 15 days from receiving that notice to request a hearing. If no hearing is requested, the suspension typically begins on the 40th day after the notice was served.

For someone depending on a car to get to work: the ALR deadline can be the difference between keeping a job and scrambling for rides. Read more about how to preserve your driving privileges under ALR rules, and if you want the official portal for filing a request, the Texas Department of Public Safety provides the Texas DPS ALR hearing portal and 15-day deadline information.

Typical ALR suspension ranges for adults:

• Test failure (0.08+): About 90 days for a first administrative action; longer if there’s a prior within certain timeframes.
• Test refusal: About 180 days for a first refusal; longer with prior actions.

If your license is suspended, you may be eligible to seek an occupational license to drive for essential needs like work and child care. Requirements vary by court and history.

Micro‑story: a Houston workday that got complicated

Imagine this: You’re a mid‑30s project supervisor in Harris County. You had two beers at a late client meeting, felt fine, and drove home. A patrol unit stopped you for a wide turn near Highway 290. You did the roadside tests, then took a breath test at the station—result shows 0.09. You’re released the next morning with a court date and a notice about your license. You’re worried: if you miss time for court or lose your license, your job could be on the line.

Here’s what your situation illustrates: a 0.09 is just over the legal limit. The reading might be affected by timing, device procedures, or medical factors. The 15‑day ALR window is now open. You’re not alone in juggling work, family, and these deadlines—but the clock is real, and getting accurate information early helps you protect your schedule and employment.

Common misconception vs. reality

• Misconception: “If I blew over 0.08, I’m automatically guilty and nothing else matters.”
• Reality: The legal limit defines “per se” intoxication, but the State still must prove the number is reliable and obtained lawfully. Breath machines require maintenance and proper observation periods; blood tests require validated methods and an unbroken chain of custody. Officer observations, body‑worn camera footage, field‑sobriety instructions, and medical conditions are all pieces that can change the picture.

How courts apply the intoxication definition beyond the number

Texas also uses a functional definition of intoxication: not having the normal use of your mental or physical faculties because of alcohol, a drug, or a combination. That means a prosecutor can pursue a DWI even if no test exists, or if your BAC is under 0.08, by arguing you lost your normal faculties. Conversely, if the State’s 0.08+ number is shaky, the per se theory can be challenged.

For a working adult trying to keep a steady schedule, the takeaway is simple: the number matters, but context matters too. Bodycam video, dash‑cam angles, lighting, weather, instructions given, footwear, and medical history can all feed into the “faculties” analysis the jury or judge actually sees.

Evidence that matters if your job is on the line

For the Solution‑aware reader: the quality of your evidence often drives outcomes. Key items include:

• Breath‑test records: instrument certification, maintenance logs, simulator solution records, and the 15‑minute observation period.
• Blood‑test trail: phlebotomy documentation, preservative and anticoagulant checks, gas chromatography validation, analyst credentials, and chain of custody.
• Traffic stop basis: reason for the stop, probable cause for arrest, and whether instructions on field tests were accurate.
• Video and audio: full‑length body‑worn camera and dash‑cam footage, not just clipped highlights.
• Medical factors: reflux, diabetes (acetone), injuries, neurological conditions, or fatigue that can mimic impairment clues.

One sentence for the Solution‑seeking Professional in particular: data like calibration logs, gas‑chromatography validation runs, and body‑camera sequences often carry more weight than a single BAC number in isolation.

What different BAC ranges can mean in real life

Numbers are shorthand, not destiny, but here’s a practical guide to how Texas ranges are usually viewed:

BAC or Situation	How Texas Frames It	What You Might Experience
0.00–0.079	Below per se limit	Case may focus on officer observations; video becomes critical. Acquittals and dismissals are possible depending on the facts.
0.08–0.149	Per se DWI	Class B range. Prosecutors rely on the number plus driving facts. ALR suspension for test failure is common unless a hearing is won.
0.15+	High‑BAC enhancement	Class A range. Expect stricter bond conditions and potential ignition interlock during the case.
CDL at 0.04+ (in CMV)	Lower per se standard for commercial driving	Even non‑work DWIs can affect CDL status. Employment consequences can be severe.
Under 21 with any alcohol	Zero‑tolerance style rule	May face license consequences and alcohol education; different from adult DWI standards.

Penalties, work, and insurance: what to expect

In Houston‑area courts, first‑offense cases often involve a mix of fines, court costs, community service, alcohol education, and possible probation. For 0.15+, ignition interlock is commonly ordered as a condition of bond or probation. A DWI can raise insurance costs for several years, and many employers ask about pending charges or license status before approving fleet car use or certain job sites.

To get a sense of common ranges and add context to your risk assessment, review the summary of penalties and possible consequences for different BAC levels. Remember: these are ranges, not guarantees, and outcomes depend on facts and evidence.

Administrative steps in the first 48 hours (educational checklist)

If you’re worried about missing work or losing the ability to drive to your job site, use this educational checklist to get organized:

• Mark the 15‑day ALR deadline from the date you received the suspension notice; track when the 40‑day temporary period ends.
• Gather paperwork: bond receipt, court date notice, temporary driving permit, tow/impound receipt, and any property vouchers.
• Write your timeline while it’s fresh: where you were, what you drank, when you stopped drinking, traffic conditions, and names of potential witnesses.
• Save medical and prescription info that could affect BAC or field tests (GERD, diabetes, injuries, sleep deprivation).
• Preserve video evidence immediately if possible: some businesses and apartments overwrite footage within days.
• Consider requesting police reports, breath‑test records, and body‑worn camera files as soon as they are available to you.
• If your license is at risk and you need to drive for work, learn the basic requirements for an occupational license should that become necessary.

Notes for different readers

Solution-seeking Professional: You’ll want to focus on the evidence—breath‑machine maintenance, gas‑chromatography validation for blood, and video timelines. These items can shape negotiations or trial strategy more than the headline BAC number.

Casual/Younger Driver: The cost of a DWI goes far beyond a ticket. Even a first offense can mean license issues, hundreds in fees, higher insurance, and time away from school or work. Catch an Uber or call a friend—one ride can save you thousands.

Career-focused Executive: Ask early about court schedules, remote appearances, and document handling to protect your calendar and discretion. Background checks and professional‑license boards often care about outcomes and timelines; plan ahead.

High-net-worth/Well-informed: Consider the long tail: data privacy, lab discovery, and collateral consequences for travel or licensing. Evidence retention letters and structured discovery requests can matter as much as any courtroom moment.

Understanding the Texas intoxication definition and alcohol concentration

Texas’s definition of intoxication centers on “alcohol concentration” and the loss of normal faculties. Alcohol concentration is typically expressed as grams of alcohol per 210 liters of breath or per 100 milliliters of blood. That’s why breath and blood test results are considered interchangeable for legal purposes, even though the science and procedures behind them are different.

For the working adult reader: if you’re reading this because you’re afraid of losing your job, the key step is simple—separate the legal definition from your real life. The law uses thresholds and elements. Your life uses calendars, car keys, and child‑care pickup times. Treat the legal limit as one piece in a larger plan to stabilize your license and schedule while you sort out the evidence.

Field sobriety tests vs. BAC: why both show up in reports

Officers use standardized field sobriety tests (like the walk‑and‑turn) to build probable cause. These tests are not the same thing as a BAC test, and they can be influenced by nerves, injuries, footwear, or the testing surface. Video often tells a more complete story than a checkbox form. If your BAC is close to 0.08, these details may matter even more.

Frequently asked questions about the Texas driving while intoxicated blood alcohol level

Is 0.08 the only way to get a DWI in Texas?

No. Texas allows a DWI based on either a BAC of 0.08 or higher (per se) or proof that you lost the normal use of your mental or physical faculties due to alcohol or drugs. The officer’s observations and video can be used even without a test result.

What happens in Houston if my BAC is 0.15 or higher?

A 0.15+ result triggers a high‑BAC enhancement that increases the charge to a higher misdemeanor class. Expect stricter bond conditions and a stronger push for ignition interlock while the case is pending in Harris County courts.

How quickly can my Texas license be suspended after a DWI arrest?

You typically have 15 days from receiving the suspension notice to request an ALR hearing. If no hearing is requested, the suspension generally starts on the 40th day after notice and can last about 90 days for a test failure or about 180 days for a refusal, depending on history.

Will a first DWI cost me my job?

It depends on your role and employer policies. Many jobs care most about license status and schedule reliability, so handling the ALR deadline and court dates promptly can reduce disruption to your work.

Does a DWI ever come off my record in Texas?

Texas does not have automatic expunction for a DWI conviction. Some non‑conviction outcomes may qualify for expunction or orders of nondisclosure, but eligibility is fact‑specific and time‑dependent under Texas law.

Why getting informed early matters

Here’s a clear stance: early, accurate information reduces harm. The 15‑day ALR timer is short. Evidence (like surveillance video) can disappear. Work schedules get tighter around court dates. Taking organized, informed steps in the first two weeks helps you protect your license, your job, and your options. If you have questions about your particular facts, consider speaking with a qualified Texas DWI attorney for guidance tailored to your situation.

Butler Law Firm - The Houston DWI Lawyer
11500 Northwest Fwy #400, Houston, TX 77092
https://www.thehoustondwilawyer.com/
+1 713-236-8744
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