Clinically reviewed by Clint Kreider, MS, LMFT, Clinical Director at Harmony Junction Recovery. · Reviewed October 2026
Short answer: Rehab usually lasts anywhere from 30 to 90 days or more, depending on the level of care, the substance and your progress. Medical detox typically takes a few days to about a week, residential treatment commonly runs 30, 60 or 90 days, and outpatient care can continue for several months. The National Institute on Drug Abuse (NIDA) notes that most people need at least three months of treatment to significantly reduce or stop drug use, and longer treatment is linked to better outcomes.
How long does each level of care last?
| Level of care | Typical length | What it involves |
|---|---|---|
| Medical detox | 3–10 days | 24/7 medical monitoring and medications to manage withdrawal safely |
| Residential / inpatient | 30–90 days | Live on site; daily individual and group therapy |
| Partial hospitalization (PHP) | 2–6 weeks | Full days of treatment, home or sober living at night |
| Intensive outpatient (IOP) | 8–12 weeks | A few hours a day, several days a week; compatible with work |
| Aftercare | Months to ongoing | Outpatient sessions, support groups, sober living, MAT follow-up |
Most people move through several levels — for example detox, then residential, then IOP — so the full episode of care is longer than any single stage.
Is 30 days of rehab enough?
For some people, a 30-day residential stay followed by outpatient care is enough to build a stable start. For many others, especially after long-term use, opioid or fentanyl dependence, or a co-occurring mental health condition, 60–90 days of structured care gives better results. What matters is the total time in treatment, not only the residential portion. Learn what happens in a 30-day program.
How long does detox take by substance?
- Alcohol: symptoms usually start within 6–24 hours, peak around days 1–3, and settle within about a week. Severe withdrawal can be dangerous and needs medical supervision. See alcohol rehab and detox.
- Opioids and fentanyl: short-acting opioids typically cause withdrawal for 5–10 days; MAT can reduce symptoms and cravings. See fentanyl detox.
- Benzodiazepines: require a gradual, medically managed taper that can take weeks; stopping suddenly can cause seizures.
- Stimulants (cocaine, meth): physical withdrawal is shorter, but low mood, fatigue and cravings can last weeks. See cocaine rehab.
What affects how long rehab takes?
- The substance, how much and how long it has been used
- Co-occurring conditions such as depression, anxiety, PTSD or bipolar disorder (dual diagnosis)
- Previous treatment attempts and relapses
- Physical health and medical complications
- Your home environment, support system and work or family commitments
- Insurance authorization — your plan may approve care in stages based on medical necessity
Are longer programs more effective?
Generally, yes. NIDA’s Principles of Drug Addiction Treatment state that staying in treatment for an adequate period is critical and that outcomes improve with longer treatment. Longer programs give time to stabilize physically, work through underlying issues in therapy, practice coping skills in real life and build an aftercare plan before support is reduced.
Frequently asked questions
Can I leave rehab early?
Voluntary treatment means you can leave, but leaving against clinical advice raises the risk of relapse — and of overdose if tolerance has dropped. Talk to your treatment team first; stepping down to a lower level of care is usually safer than stopping altogether.
Will insurance pay for 60 or 90 days?
Many PPO plans cover multiple levels of care when they are medically necessary, often with authorizations reviewed along the way. Learn how insurance covers rehab or call us for a free benefits check.
How long is rehab if I have a job?
Many people use medical leave for detox and residential care, then step down to IOP after returning to work. See going to rehab without losing your job.
Not sure how much treatment you need? Our admissions team can do a free, confidential assessment and verify your insurance. Call (855) 906-4088 24/7.
Sources: National Institute on Drug Abuse (NIDA), Principles of Drug Addiction Treatment: A Research-Based Guide; American Society of Addiction Medicine (ASAM) Criteria; SAMHSA.