The amount of time you will end up in therapy and the number of sessions you will need depends on what issues you have, and what sort of therapy you have decided to try.
Short-term and Structured Therapies
Short-term therapies (also called 'time limited', or 'brief' therapy) are the most structured forms of therapy. You will decide in your first few sessions just how many therapy sessions you will commit to. This can range from between four to 16 weekly sessions.
At the end of the agreed time frame it does not mean that your therapy has to end. If you and your therapist agree that your issues could benefit from another round of sessions, you simply make a new contract.
Short-term therapies include cognitive behavioural therapy (CBT), mindfulness-based cognitive therapy (MBCT), dynamic interpersonal therapy (DIT), emotionally focused therapy (EFT), cognitive analytical therapy (CAT), and solution-focused brief therapy (SFBT).
Counselling
Counselling tends to be shorter-term than psychotherapies. And sometimes, depending on the type of counselling, you might agree at the beginning on the number of weekly sessions you'll start with.
Long-term or 'Depth' Psychotherapy
Long-term psychotherapies are open-ended. Often the work goes on weekly for several years or more. This is not surprising when these types of therapies (psychodynamic psychotherapy, existential psychotherapy, schema therapy, etc) delve into your childhood and past.
You work together until you as a client feel you've had the results you want, or are ready to take a break. Sometimes it's the therapist who will suggest you are ready to try phasing out therapy, and if you agree you start to wrap up your work together.
Psychoanalytical Therapy and Jungian Therapy
Most modern psychotherapies demand a weekly committment. But there are exceptions.
Psychoanalytical psychotherapy, or 'psychoanalysis', is the oldest form of psychotherapy, started by Freud himself (although since improved on by many other leading thinkers). It requires you to attend several sessions a week. This is often three sessions weekly, and even up to five in some cases.
Jungian therapy arose as a response to psychoanalysis (Jung was originally friends with Freud but then their opinions differed). And indeed some Jungian therapists require a smiliar commitment of several sessions a week.
Nervous to commit to therapy?
Therapy is not a jail sentence. Even if you start a long-term depth psychotherapy, you are free to leave whenever you want. Don't see trying a type of therapy that ends up not quite right for you as time wasted. It gives you clarity on your real issues and needs, meaning you are more likely to find the right therapy than before.