Key answer
There is no single correct rehab length. Residential stays are one phase of care; duration should reflect risk, progress and practical needs, while continuing treatment and recovery support often extend for months or longer.
Why fixed numbers can mislead
A 7-, 14-, 28-, 30- or 90-day package is an administrative offering, not a universal clinical dose. Two people using the same substance may need different withdrawal care, psychiatric assessment, therapy pace and discharge support.
What affects duration
- withdrawal and medical stability;
- severity and duration of the disorder;
- overdose or relapse history;
- co-occurring mental-health conditions;
- cognitive or trauma-related needs;
- home environment and support;
- response to treatment; and
- availability of safe follow-up.
Residential care is not the whole pathway
A short residential stay can be useful when it connects directly to medication, therapy, outpatient care, peer support and practical recovery arrangements. A long stay can still fail if discharge is abrupt or the home environment is unchanged.
Questions to ask a center
How is extension decided? Can the program shorten when goals are met? What happens if medical or psychiatric needs exceed the facility’s scope? Which continuing-care appointments are booked before departure? What costs are added if the stay changes?
Be cautious with cure promises
No credible provider can guarantee lifelong recovery after a fixed number of days. Ask how outcomes are defined, measured and followed, and how people lost to follow-up are handled.