Delaware DUI Laws: Penalties, BAC Limit & License (2026)

In Delaware the offense is called driving under the influence (DUI), and Title 21, Section 4177 of the Delaware Code makes it unlawful to drive with an alcohol concentration of 0.08 or more, or while under the influence of alcohol or drugs. A first DUI is a misdemeanor punishable by a fine of $500 to $1,500, up to 12 months in jail, a license revocation, and a mandatory ignition interlock device.

This guide is part of our DUI Laws by State series.

What counts as a DUI in Delaware

Delaware's core DUI statute, Title 21, Section 4177, makes it unlawful to drive a vehicle while under the influence of alcohol or drugs, or with an alcohol concentration of 0.08 or more within four hours of driving. The four-hour rule is unusual: the State can use a test taken up to four hours after driving and relate it back, so a driver does not avoid the per se charge simply because the test came later. A driver can also be convicted under the impairment prong below 0.08 if alcohol or drugs affected the ability to drive safely. Commercial drivers face a 0.04 limit, and drivers under 21 fall under a zero-tolerance rule that makes it unlawful to drive with an alcohol concentration of 0.02 or more. The 0.08 figure is the federal benchmark adopted by every state except Utah, which sets its limit at 0.05, as reflected by the National Highway Traffic Safety Administration.

First-offense DUI penalties in Delaware (jail, fines, suspension)

A first DUI under Section 4177 is a misdemeanor. Under Section 4177(d)(1), the penalty is a fine of not less than $500 nor more than $1,500, or imprisonment of not more than 12 months, or both, and any period of imprisonment may be suspended. Most first offenders avoid jail through suspended time and probation, but the conviction still triggers a license revocation handled by the Delaware DMV and a mandatory ignition interlock term. The court also orders an alcohol evaluation and a course of instruction or rehabilitation. Eligible first offenders may instead elect the First Offender Election under Section 4177B, a one-time diversion that requires completion of an evaluation and program in lieu of a trial, available only if the BAC was under 0.15, no injury occurred, and the driver had a valid license.

Watch out: The DMV revocation and the criminal court case are two separate proceedings. You can resolve the criminal case and still lose your license through the DMV, and you generally must request a DMV hearing within 15 days of the arrest notice to contest the administrative revocation.

Ignition interlock requirements in Delaware

Delaware requires an ignition interlock device (IID) for every DUI offender, including first offenders, under Section 4177G and the statewide IID program that became mandatory on February 1, 2015. After serving a minimum mandatory period of revocation, a first offender installs the device to obtain an IID-restricted license and resume driving, typically about 45 days from the effective date of the revocation. The device requires a breath sample before the engine starts and at random intervals while driving, and it logs every reading for the DMV. The required IID term scales up for repeat offenders. Delaware's all-offender approach means there is no low-BAC exception, so a driver convicted at exactly 0.08 still installs the device.

License revocation and the administrative process in Delaware

Delaware runs two tracks against the driving privilege at the same time. The administrative revocation is an immediate DMV action based on the arrest, independent of the criminal court outcome, as the Delaware DMV explains. Under Title 21, Section 2742, a driver who takes and fails the chemical test on a first DUI loses the license for 3 months, a second offender for 1 year, and a driver with more than two offenses for 18 months. The arresting officer serves a notice of revocation that also acts as a temporary permit, and the revocation takes effect unless the driver requests a hearing within 15 days. A criminal conviction can carry its own revocation. To reinstate, a driver must serve the revocation, complete the required course, install the IID, and pay reinstatement fees.

Repeat offenses and the Delaware look-back period

Delaware counts a prior DUI within a 10-year window to enhance a second offense under Section 4177(d)(2), so a second conviction within 10 years carries higher mandatory fines, jail exposure, and a longer revocation. For third and later offenses, the enhancement is even broader: the statute counts prior DUI convictions regardless of how long ago they occurred, so an old conviction can still elevate a new charge. The felony threshold sits at the third offense, which is a Class G felony under Section 4177(d)(3), and fourth, fifth, and later offenses climb to higher felony classes with mandatory prison time. A DUI that causes serious injury or death can be charged as a felony, such as vehicular assault or vehicular homicide, regardless of offense number.

Watch out: Refusing a chemical test does not avoid a revocation and usually makes it worse. A first refusal results in a 12-month revocation under Section 2742, far longer than the 3-month revocation for failing the test, and the refusal can be used against you in court.

Refusing a breath or blood test in Delaware

Delaware's implied-consent law means that by driving in the state, you have agreed to submit to a chemical test of blood, breath, or urine if lawfully arrested for DUI. According to Title 21, Section 2742, a first refusal results in a 12-month license revocation, a second in 18 months, and a third or subsequent in 24 months. These refusal revocations are administrative and apply on top of any criminal penalties. Because the 12-month refusal revocation is four times the 3-month revocation for failing the test, refusing rarely helps and often hurts. The driver may contest the revocation at a DMV hearing requested within 15 days of the notice, but missing that deadline generally forfeits the chance to fight it.

Can you expunge or seal a DUI in Delaware

Delaware does not allow DUI convictions to be expunged. The state's expungement statute, Title 11, Chapter 43, Subchapter VII, excludes offenses under Title 21, and because DUI is codified in Title 21 (Section 4177), a DUI conviction is categorically barred from both mandatory and discretionary expungement. The practical workaround is the First Offender Election under Section 4177B: an eligible first offender who completes the program in lieu of trial avoids a conviction in the first place, which keeps a DUI off the criminal record. That election is a one-time option with strict eligibility, requiring a BAC under 0.15, no injury, no prior offense, and a valid license. If a DUI charge is dismissed or results in an acquittal, the arrest record may be eligible for expungement, but a conviction cannot be erased.

What to do after a DUI arrest in Delaware

A Delaware DUI generates two cases at once: a criminal case in court and an administrative license case at the DMV. The deadlines are short, so a common first step is to request a DMV hearing within 15 days of the arrest notice, because missing that window generally means the revocation takes effect automatically. The criminal case proceeds on its own schedule through arraignment, case review, and resolution. General information cannot tell you how your case will come out, since the outcome depends on the specific facts, the evidence, and your record. Many people consult a licensed Delaware DUI attorney to understand the charge, the 15-day deadline, the First Offender Election option, and the path through both the court case and the DMV case. Keep the arrest paperwork, the notice of revocation, and any test results in a safe place.