That depends on the person in therapy, why they have PTSD (panic attacks, flashbacks, nightmares, anxiety, depression), and what they are willing to do to take care of it (therapy is only as good as what the client puts into it. A therapist cannot fix a person. Sometimes it takes time for the client to realize this and that 98% of therapy is the person doing things on their own like therapy "homework", journal writing, sometimes a workbook or two, and so on. Someone who is not willing to answer questions and talk about what is wrong and do suggested activities and homework is not going to get anywhere and may need more possibly years of therapy then someone who goes into it with the attitude of I don't like what is happening and I want it gone and I will do anything to get rid of it who will need less amount of therapy time. Sometimes people go into therapy and everything gets taken care of and ends therapy sessions and then something in their life sends the PTSD symptoms back out of control so the person needs to enter therapy again.

If the person is court mandated into therapy they must attend therapy until the court releases them from therapy based on the therapists reports.

People in therapy on their own - Some only need a few sessions and others need years worth of sessions. Some go for a while and then take a break and then go back.

Basically the criteria for not needing any more therapy is set by the person in therapy and the therapist that they are seeing. Therapy ends when one or both feel that the PTSD symptoms are in control. They no longer have frlashbacks, nightmares, panic attacks or they can handle them without needing their therapists helpby using their new coping tools learned in therapy.

I have been in and out of therapy for 23 years.