Class 1 Felony in Illinois: Charges, Sentencing, and Defense

What Is a Class 1 Felony in Illinois?

A Class 1 felony is the second most serious category of criminal offense under Illinois law, ranking behind only first-degree murder and Class X felonies. Under 730 ILCS 5/5-4.5-30, a Class 1 felony conviction carries a determinate prison sentence of 4 to 15 years, with limited exceptions for second-degree murder and extended-term sentencing.

Class 1 felonies include many of the most consequential charges a person can face outside of murder, including criminal sexual assault, residential burglary, large-volume drug offenses, and certain violent crimes involving firearms.

Class 1 Felony vs Others

Illinois divides felonies into five tiers. First-degree murder is its own category, followed by Class X, then Class 1, Class 2, Class 3, and Class 4 in descending order of severity. A Class 1 offense sits near the top of that ladder, above the majority of felony charges filed in the state, and reserved for crimes the legislature has determined cause the most serious harm short of killing.

If you have been charged, our criminal defense team can explain where your specific charge falls and what that means for your case.

Class 1 Felony Offenses in Illinois

The Class 1 classification is assigned by statute, not by prosecutor discretion. Some offenses are Class 1 by default. Others escalate into Class 1 based on circumstances: the weight of drugs involved, the dollar value of stolen property, the identity of the victim, or the presence of a weapon.

Below are the most common Class 1 felony offenses our firm defends in DuPage County and across Greater Chicago. Click any charge for detailed defense information.

This is not an exhaustive list. Many Illinois offenses can be charged as Class 1 felonies depending on the facts of the case, prior convictions, or statutory enhancements. If you have been charged with any offense you suspect is a Class 1 felony, call us to discuss the specific statute and what it means for you.

Class 1 Felony Sentencing in Illinois

The sentencing framework for a Class 1 felony is set by 730 ILCS 5/5-4.5-30. Judges have discretion within the statutory ranges, but the outer limits are fixed by law. The examples below are and will not be the same for every one so you’re best to speak with a lawyer to understand what you’re actually up against.

Prison term

A Class 1 felony conviction carries a determinate prison sentence of 4 to 15 years in the Illinois Department of Corrections (IDOC). The only exception within the Class 1 category is second-degree murder, which is sentenced from 4 to 20 years.

Fines and restitution

The court may impose fines of up to $25,000, plus restitution to victims as required by 730 ILCS 5/5-5-6. Fines are in addition to any prison sentence and can be a significant long-term financial burden independent of incarceration.

Mandatory supervised release

Every Class 1 felony prison sentence includes a 2-year term of mandatory supervised release (MSR) following release from IDOC. MSR was formerly called parole and operates similarly. A violation can send you back to prison to finish the original sentence.

Extended term sentencing

Certain aggravating factors extend the sentencing range to 15 to 30 years. Under 730 ILCS 5/5-8-2, extended terms apply when the defendant has a prior felony conviction of the same or higher class within 10 years, when the offense was committed against a victim under 12 or over 60, when hate-crime factors apply, and in several other enumerated circumstances.

Is a Class 1 Felony Probationable in Illinois?

For most Class 1 felonies, probation is a legally available sentence, but it is not automatic. Under 730 ILCS 5/5-4.5-30(d), the court may impose probation or conditional discharge of up to 4 years in lieu of prison for many Class 1 offenses.

When probation is available

The court has discretion to grant probation for most Class 1 felonies when it determines incarceration is not required to protect the public. Drug court and home detention are also available as alternatives in qualifying cases under 730 ILCS 5/5-8A-3. A strong defense uses every available pathway to keep a conviction from becoming prison time.

When probation is barred

Probation is not available in two situations. First, if the Class 1 offense was committed while the defendant was already serving probation or conditional discharge for another felony, probation is barred by statute. Second, several specific Class 1 offenses, including certain criminal sexual assault convictions, are non-probationable under the offense statutes themselves.

What the court weighs at sentencing

Judges consider the nature and circumstances of the offense, the defendant’s prior criminal history, acceptance of responsibility, evidence of rehabilitation, and the likelihood of compliance with probation terms. Mitigation matters. Employment, family obligations, mental health treatment, and community support can meaningfully shift a sentencing outcome when presented effectively. A prepared, persuasive sentencing memorandum is often the difference between probation and prison.

Class 1 Felony Illinois First Offense: What to Expect

A first Class 1 felony charge does not guarantee prison. It also does not guarantee probation. What happens depends on the offense, the strength of the evidence, the venue, and the quality of the defense presented.

Many first-time Class 1 offenders without a significant criminal history are legally eligible for probation where the offense statute permits it. Whether the court grants probation in a specific case depends on mitigation, the prosecution’s sentencing position, and the judge assigned. The charging decision and the plea negotiation usually shape the outcome more than trial does, because most felony cases in Illinois resolve through negotiation before reaching a jury.

Felony charges arising in DuPage County are typically heard in the 18th Judicial Circuit Court in Wheaton. Cases in Cook, Kane, Will, and Kendall counties follow each county’s own felony division procedures. Local familiarity matters. Prosecutors, judges, and local rules vary meaningfully from one county to the next.

Can a Class 1 Felony Be Expunged in Illinois?

For most Class 1 felony convictions in Illinois, expungement is not available. This is the direct answer most people need first. Sealing, a different and more limited remedy, may be possible for certain Class 1 convictions after a waiting period, but many Class 1 offenses are statutorily excluded from both expungement and sealing.

When sealing may be possible

Sealing a Class 1 conviction generally requires completion of the full sentence including MSR, a waiting period of 3 years after completion, and that the offense is not on the statutory exclusion list. Drug offenses are more commonly eligible for sealing than violent or sex-related Class 1 offenses.

Why the specific offense matters more than the class

Eligibility depends far more on which Class 1 offense was charged than on the classification itself. A Class 1 drug conviction may be sealable under the right circumstances. A Class 1 sex offense typically is not, and may also require permanent sex offender registration regardless of any record-clearing attempt.

Learn more about expungement and record sealing in Illinois.

Long-Term Consequences Beyond the Sentence

Prison time and fines are only part of what a Class 1 felony conviction costs. The collateral consequences follow you long after the sentence ends, and they shape where you can live, work, travel, and raise a family.

A felony conviction creates a permanent criminal record in nearly all Class 1 cases. It terminates firearm rights under both Illinois and federal law. It creates barriers to many forms of employment, occupational licensing, and educational programs. It affects housing applications, loan eligibility, and rental approvals. For non-citizens, a Class 1 felony can trigger deportation, inadmissibility, or permanent bars to citizenship. If the underlying offense is a qualifying sex offense, sex offender registration applies, in some cases for life.

These consequences are reason enough to fight the charge aggressively from day one, not to accept a plea that resolves the immediate case at the cost of your future.

How Dolci Weiland & Sendlak Defends Class 1 Felony Charges

Patrick J. Weiland spent nearly 10 years as a DuPage County Assistant State’s Attorney prosecuting DUI and felony cases before joining the defense side. He knows exactly how Class 1 felonies are built by prosecutors, which evidence they rely on, which weaknesses they quietly work around, and where a prepared defense can take a case apart.

The defense process

Every Class 1 case we take on starts with a complete review of the charging documents, police reports, discovery materials, and any video or forensic evidence. We file motions to suppress evidence obtained in violation of the Fourth, Fifth, or Sixth Amendments. We challenge witness credibility, chain of custody, and probable cause. When the facts call for it, we build a mitigation package for sentencing that goes well beyond what the prosecution sees. And when a plea is the right outcome, we negotiate from a position of preparation rather than pressure.

Our DuPage County advantage

Our firm has practiced in the 18th Judicial Circuit Court in Wheaton for more than three decades. We know the local prosecutors, the sentencing tendencies of the felony division judges, and the specific procedures DuPage County follows that differ from Cook, Kane, Will, and Kendall counties. That familiarity translates directly into better outcomes for our clients.