Quick Answer
Rehab length varies by type: detox is 3–10 days, short-term residential is 28 days, longer-term is 60–90+ days, and outpatient (IOP) runs 8–12 weeks. NIDA research recommends a minimum of 90 days for significant, lasting behavioral change. The 28-day model is common because of insurance, not because of evidence. Longer stays consistently produce better outcomes across substances.
Duration by Program Type
Medical stabilization only. Not a substitute for treatment.
The insurance-driven standard. Often insufficient alone, works best as step-down start.
Better outcomes than 28-day. Allows deeper behavioral work and longer stabilization.
Best evidence base. NIDA-recommended minimum for lasting change.
9+ hours/week, living at home. Then transitions to standard outpatient.
Maintenance and relapse prevention after higher-intensity programs.
What is the standard length of residential rehab?
Standard residential rehab lengths: 28–30 days (short-term, the classic 'month of rehab'), 60 days (moderate), and 90 days (long-term residential, most evidence-backed for sustained outcomes). NIDA recommends a minimum of 90 days of treatment for most people with significant substance use disorders, based on research showing that outcomes improve substantially with longer treatment duration. The 28-day model exists primarily for insurance and practical reasons, not because it represents optimal treatment duration. For severe or long-duration addiction: 6-month to 12-month therapeutic communities are available and have strong outcome data.
Does rehab length affect success rates?
Yes, treatment duration is one of the strongest predictors of recovery outcomes. Research consistently shows: outcomes improve substantially at 90 days vs. 30 days. Completion matters more than length, completing 30 days fully is better than leaving 90-day program at day 45. NIDA research: people who remain in treatment for longer than 3 months are more likely to achieve sustained abstinence. For opioid use disorder: duration of medication-assisted treatment (buprenorphine, naltrexone) matters more than residential duration, long-term MAT significantly outperforms short residential programs. The '28 days fixes it' model is not supported by outcome research.
What happens in the first week of rehab?
First week of rehab: medical assessment (psychiatric evaluation, medical history, substance use history, co-occurring conditions screening), detox if needed (medically supervised withdrawal management. Most residential programs integrate or arrange detox), orientation (program schedule, rules, expectations, meeting other residents and staff), individual assessment (treatment plan development, identifying personal goals, triggers, history), and first therapy sessions (individual and group). Emotionally: many people feel a combination of relief (being safe, having structure) and anxiety or discomfort (withdrawal symptoms, unfamiliar environment, beginning to face the addiction). The first week is the most physically and emotionally intense.
What is intensive outpatient program (IOP) and how long does it last?
IOP, Intensive Outpatient Program: a structured outpatient treatment option typically involving 3–5 days per week, 3–4 hours per day (often evenings to allow work or family obligations), for 8–12 weeks. IOP provides: group therapy (the core component), individual therapy, psychiatric services, family programming, and relapse prevention skills. IOP is appropriate for people who don't need 24-hour supervision (medically stable, safe home environment) and need more structure than standard weekly outpatient therapy. Evidence: IOP outcomes are comparable to residential for many people when motivation is high and home environment is supportive. Cost is significantly lower than residential.
What is a partial hospitalization program (PHP) and how long does it last?
PHP, Partial Hospitalization Program: the most intensive outpatient level, involving 5–7 days per week, 6–8 hours per day. PHP bridges the gap between residential and IOP. Appropriate for: people stepping down from residential who need continued intensive support, people who need intensive treatment but have stable housing, or people for whom full residential is not possible. PHP provides: daily group therapy, individual therapy, medication management, structured daily schedule. Duration: typically 2–4 weeks of full PHP, often transitioning to IOP. Combined PHP→IOP sequences are a common and effective treatment pathway that can approach residential outcomes at lower cost.
How long is detox before rehab starts?
Detox duration varies by substance: alcohol (3–7 days, withdrawal peaks at 24–72 hours, risk window closes at about 7 days), opioids (short-acting like heroin: 4–7 days, long-acting like methadone: 10–21 days), benzodiazepines (7–14+ days, slow medical taper, not abrupt cessation), stimulants (cocaine/meth: 1–3 days acute, 1–2 weeks for post-acute symptoms), and cannabis (3–10 days for acute phase). Medical detox is strongly recommended for alcohol and benzodiazepines (risk of fatal seizures with abrupt cessation). Residential rehab often incorporates detox, treatment continues seamlessly after the detox phase rather than requiring a separate facility.
What happens after residential rehab ends?
After residential rehab: continuing care (the research-backed critical period). The transition from residential to daily life is one of the highest-risk periods in recovery, structure, accountability, and support drop dramatically. Evidence-based continuing care: step-down to PHP or IOP (maintaining intensive structure during the transition), outpatient therapy (weekly individual therapy, group therapy), peer support (12-step meetings or SMART Recovery daily initially), alumni programs (many residential programs offer ongoing connection with the recovery community), sober living housing (structured, substance-free living environment, voluntary), and regular medication management if using MAT. Discharge planning should begin early in residential treatment, not on the final day.
What is the difference between 30, 60, and 90-day rehab?
30-day rehab: often insurance-limited, may be appropriate for milder cases or first-time treatment, research shows significantly higher relapse rates vs. longer programs. 60-day rehab: provides more time for trauma processing and skill-building, more complete detoxification from some substances (particularly long-acting), and longer exposure to recovery community. 90-day rehab: most strongly evidence-supported, allows addressing underlying mental health conditions, completing multiple trauma processing cycles, building robust recovery skills, and more stable transfer to continuing care. Practical consideration: longer programs cost more and require more time away from work and family, but against the cost and harm of continued addiction, they typically represent significant value.
Can I leave rehab early?
Leaving rehab early (AMA, against medical advice): most residential programs are voluntary, you can leave. Consequences: significantly higher relapse risk (the period right after leaving early is among the highest-risk in recovery), loss of progress made in treatment, and potentially the need to restart entirely. Why people leave early: discomfort with the process (withdrawal, emotional work), family or work obligations, feeling 'cured' prematurely, or the pull of ambivalence about recovery. What to do if you're considering leaving: discuss with your treatment team before leaving. They can problem-solve the specific issue. If you do leave AMA: re-engage with some level of care immediately, and discuss stepping back to a higher level if the leaving precipitates a relapse.
Does insurance cover rehab?
Insurance coverage for rehab: under the Mental Health Parity and Addiction Equity Act (MHPAEA) and the Affordable Care Act (ACA), health insurance is required to cover substance use disorder treatment at parity with medical/surgical benefits. In practice: most insurance plans cover medically necessary detox, residential (often 28–30 days unless extended stay is justified), IOP, and outpatient therapy. Prior authorization is often required. Coverage details vary widely by plan, call your insurance's behavioral health line before admission. No insurance: SAMHSA's treatment locator (findtreatment.gov) lists sliding-scale and publicly-funded programs. Medicaid covers SUD treatment in all states, ACA plans have SUD coverage.
What should I bring to rehab?
What to bring to residential rehab: identification (driver's license, insurance cards), medications in original pharmacy bottles, comfortable clothing for 30–90 days (laundry available), basic toiletries (check facility's allowed products list. Many restrict alcohol-containing products), book/journal, phone/charger (many facilities restrict use), and personal items that support recovery (photos of family, etc.). What NOT to bring: drugs or paraphernalia (will be confiscated), valuables or large amounts of cash, items not on the facility's allowed list. What facilities provide: meals, bedding, group activities, therapy materials. Call ahead for the specific allowed/not-allowed items list. It varies by program.
What are the signs that someone needs residential rehab vs. outpatient?
Residential vs. outpatient indicators: residential (higher level of care) is appropriate for: severe dependence requiring medical detox, prior outpatient treatment failures, home environment that is unsafe or unsupportive (substance-using household members, high-stress environment), co-occurring psychiatric conditions requiring 24-hour monitoring, lack of social support, history of severe relapse risk, or logistically impossible outpatient commitment. Outpatient is appropriate for: stable housing and supportive home environment, strong motivation and no prior treatment failures, less severe dependence not requiring 24-hour supervision, ability to meet significant daily commitments. ASAM (American Society of Addiction Medicine) criteria provide the clinical framework for this decision, treatment admission staff use these criteria.
How do I prepare for going to rehab?
Preparing for residential rehab: arrange work leave (FMLA, Family and Medical Leave Act, provides job-protected leave for medical treatment including SUD, HR is your starting point), make childcare arrangements, arrange pet care, pay bills that will come due, notify essential contacts (with the disclosure level you're comfortable with, you're not required to disclose details), pack the facility's allowed items list, address any pending obligations that would create anxiety during treatment, and emotionally: accept that the first week will be hard and commit to staying through the discomfort. Practical logistics handled before entry reduce the mental interference during treatment. Many facilities have an admissions team that can walk through this process.
What is medication-assisted treatment in rehab?
MAT, Medication-Assisted Treatment, in residential rehab: FDA-approved medications used alongside therapy. Opioid use disorder: buprenorphine (Suboxone) and methadone reduce withdrawal symptoms and cravings and prevent relapse, dramatically improve outcomes, naltrexone (Vivitrol) blocks opioid effects. Alcohol use disorder: naltrexone (reduces craving and relapse risk), acamprosate (reduces protracted withdrawal discomfort), disulfiram (aversive deterrent). Nicotine: varenicline (Chantix), bupropion, NRT. Evidence: MAT for opioid use disorder reduces mortality by 50% and dramatically improves retention in treatment. Programs that refuse MAT on principle are contradicting evidence-based medicine. Ask about a program's MAT philosophy before admission if this is relevant.
What is aftercare planning in rehab?
Aftercare planning in residential rehab: the process of developing a concrete plan for life after discharge, the critical bridge from residential to sustainable recovery. A good aftercare plan includes: specific step-down level of care (PHP, IOP, or outpatient), scheduled first appointments, confirmed housing (sober living or home), medication plan if using MAT, meeting attendance schedule, sponsor or support contacts, identified triggers and coping strategies, employment or daily structure plan, and crisis contact list. Aftercare planning should begin in the first week of residential treatment, not the week before discharge. Research: people with concrete aftercare plans have significantly better 12-month outcomes than those discharged without one.
Why 28 Days Isn't Enough for Most People
The 28-day model became the industry standard in the 1970s, not because research supported it, but because that's what early insurance plans covered. It persists today largely for the same administrative reasons.
The neuroscience tells a different story. In early recovery, the brain is actively recalibrating its reward circuitry, the dopamine system that has been dysregulated by chronic substance use. This process takes months, not weeks. Cravings, emotional dysregulation, and impulsivity, all elevated in early recovery, don't stabilize in 28 days.
NIDA's research consensus: treatment of less than 90 days has limited effectiveness for most people with serious addiction. 28-day programs can be a starting point, especially when followed by robust step-down care, but they should be understood as the beginning of treatment, not the whole of it.
The Continuum Approach: What Actually Works
The most effective model isn't a fixed program length, it's a continuum of progressively less intensive care matched to the person's clinical needs:
- Medical detox (3–10 days) → stabilize physically
- Residential treatment (28–90+ days) → intensive behavioral work, address underlying issues
- PHP or IOP (4–12 weeks) → maintain progress, practice skills in the real world
- Standard outpatient (ongoing) → relapse prevention, life skills, continued support
- Peer support + MAT (indefinite) → community and medication to sustain recovery
People who follow this full continuum consistently show better long-term outcomes than those who complete inpatient and return directly to daily life without step-down care.
Does Insurance Limit How Long You Can Stay?
Insurers often try to, but they can't deny medically necessary care. Under the Mental Health Parity Act, coverage for SUD treatment must be at parity with medical conditions. If your insurer pushes for early discharge while your clinical team believes you need continued stay, you have the right to appeal. A good treatment program will advocate for appropriate length of stay.
If cost is a barrier to a longer stay, ask your treatment program about sliding-scale fees, payment plans, and state-funded options. See our free addiction treatment guide.
Recovery is a long game
Whatever program you're in, the daily habits of recovery matter for years. Forge tracks your streak and helps you manage cravings long after formal treatment ends.
Download Forge FreeFrequently Asked Questions
How long does rehab last?
Detox: 3–10 days. Short-term residential: 28 days. Long-term: 60–90+ days. IOP: 8–12 weeks. NIDA recommends at least 90 days for significant behavioral change.
Is 28-day rehab enough?
For most people with serious addiction, no. NIDA research shows treatment under 90 days has limited effectiveness. 28 days works best as a starting point followed by step-down care.
Why is 90-day rehab recommended?
It provides enough time for neurological stabilization, behavioral skill development, and habit formation. Shorter stays interrupt this process before it's complete.
How long is detox?
3–10 days depending on substance and severity. Alcohol: 5–7 days. Opioids: 7–10 days. Benzodiazepines: up to 2–4 weeks. Detox alone is not addiction treatment.
What happens after rehab?
Step-down to IOP or standard outpatient, peer support groups, medication management if on MAT, and ongoing relapse-prevention work. Aftercare is critical. Most relapse occurs after leaving formal treatment.
Related: Inpatient vs. Outpatient Rehab · How to Find Rehab · How Much Does Rehab Cost?