30 Days is considered "short-term rehabilitation," and anything longer is considered "long-term rehabilitation." The only difference between rehab lengths is that treatment is more extensive in short-term rehabilitation because more treatment is being condensed into a shorter amount of time. Unlike inpatient rehabilitation, when you choose for an outpatient program, each step of the rehab procedure is generally completed at a different center.When that's finished, the real therapy can begin 90 days is typically a minimum, but many individuals continue seeing a therapist or going to group therapy for multiple years. The longer you invest in rehab, the more pricey it will be. However, those who have severe dependencies might not get all the aid that they require in short-term rehab.