One of the questions I’m commonly asked is “How long does therapy take?”. Perhaps unsurprisingly, the answer is “It depends.” Various factors such as the goals of the patient, the presenting problem, and the modality of the therapy will inform the duration of the work. As the work evolves, the amount of sessions is determined organically by both the patient and therapist. The time needed for therapy is unique to each case.

That being said, we have conventions and research that can tell us averages, which give us a rough idea. These averages can give people a sense of the kind of commitment usually required, and can help to temper expectations.

Before the development of more modern forms such as cognitive behavioural therapy (CBT) or psychodynamic therapy, psychoanalysis was the dominant method of psychotherapy. Psychoanalysis is an intensive process that is expected to take years, with the patient attending therapy 3 to 5 times a week. The justification for this, according to psychoanalysts, is that most patients come to therapy with ingrained problems that took many years to become entrenched; a patient’s personality took a lifetime to develop, and so it wouldn’t be realistic to expect significant change or insight to happen in a mere matter of weeks or months. Changing and understanding deep-rooted patterns of behaving, thinking, and relating is considered a long-term project. These patterns shift and evolve over a lifetime. To the psychoanalyst, the analysis is never “over”, only paused and revisited.

A major criticism of this approach is that years of therapy, done multiple times a week, is prohibitively expensive and time-consuming for most people. The British Psychoanalytical Society gives a rough figure of £8,000 to £14,000 per year for a full five-times-a-week analysis [1]. For this reason, psychoanalysis has a reputation for being largely a preserve of the more affluent middle-classes. This has been the case since its inception in the late 19th century. 

In the early 20th century, in part as a reaction to psychoanalysis, a new paradigm emerged in psychology: behaviourism. Behaviourism sought to understand human behaviour in terms of stimuli, reinforcement, and conditioning rather than unconscious dynamics. By the mid 20th century, the “cognitive revolution” led to an emergence of a new scientific field: the cognitive sciences. The cognitive sciences used empirical research methods and clinical studies to understand the processes of the mind. This was in contrast to psychoanalysis, which relied heavily on unfalsifiable theory and case studies to guide its practice.

Both behaviourism and the cognitive sciences were instrumental in the development of early cognitive behavioural therapy. New ways of treating mental health problems were devised, such as systematic desensitization for phobias and cognitive approaches to depression. Unlike psychoanalysis, these approaches were designed to take months, and showed promising results.

At the same time, short-term psychodynamic psychotherapies were being developed. Short-term psychodynamic work is commonly defined as work below around 40 sessions [2]. These modernised adaptations of psychoanalytic techniques were created to address the time commitments and financial costs inherent to psychoanalysis. Psychoanalytic principles were adapted to shorter time frames, with less frequent sessions. Proponents of this approach argued that although short-term psychodynamic work could never replace the “depth” of what gets done in longer-term therapy, meaningful work could still be done. A compromise was made to increase the accessibility of psychoanalytic treatments.

Therapy taking months rather than years has now established itself as the standard. But what does the research show? 

In 2001, a large study [3] (Lambert, M. J. et al., 2001) was conducted using outcome data from over 10,000 psychotherapy patients - this data was analysed to understand the association between number of treatment sessions and “clinically significant improvement”. It found that 50% of patients required 21 sessions of treatment before they met criteria for clinically significant improvement. 75% percent of patients were predicted to improve only after receiving more than 40 treatment sessions.

Another study [4] (Hansen et al., 2002), reviewing the research into treatment dosage and “meaningful change”, found that there is general consensus that between 13 and 18 sessions of therapy are required for 50% of patients to see improvement.

In ‘The Handbook of Psychotherapy & Behaviour Change’, Michael Lambert reviews the research findings [5]: He found that “75% [of patients] are predicted to need at least 14 sessions” to see “reliable improvement”.

However, patients who undergo therapy are ideally aiming for complete recovery (that is, being empirically indistinguishable from “normal” peers following treatment) rather than just improvement. The goal of complete recovery is desirable because it affords patients the maximum degree of overall well being and functioning, and greatly reduces the chances of relapse.

Lambert goes on to write about recovery in his chapter of the book [5]: “For patients who begin therapy in the dysfunctional range, 50% can be expected to achieve ... recovery after about 20 sessions of psychotherapy. More than 50 sessions are needed for 75% of patients to meet this criterion.”

Studies like the ones cited likely informed the traditional CBT model (1 hour sessions for 12 to 20 weeks [6]). Similarly, the NHS’s Talking Therapies service (formally IAPT) typically offers a maximum of 20 weekly sessions per treatment course [7], as this is likely the number of sessions needed on average for a majority of patients to see clinically significant improvement, whilst also attending to cost effectiveness.

The issue is further complicated by what qualifies as “clinically significant improvement” and “meaningful change”. To properly address this would require a separate article, but I can demonstrate to you some of the key complexities of this issue with a hypothetical example:

Let’s imagine that someone decides to start therapy because they struggle to lose weight. 

One way to approach this problem could be CBT. Judith Beck (daughter of “the father of CBT”, Aaron Beck) published an excellent book called ‘The Beck Diet Solution’, which sets out cognitive and behavioural skills to help people meet their diet goals. Following this programme, with the help of a CBT therapist, patients could set weight goals, identify triggers for overeating, and create plans to tackle cravings.

The outcome measures for this kind of therapy would be fairly straight-forward: for example, is the patient losing weight week after week? Has the frequency of overeating been reduced?

Another approach to this problem could be psychodynamic. In psychodynamic psychotherapy, the patient would of course be free to talk about the practicalities of their attempt to lose weight. The ups and downs, what has worked and what has not. This can be helpful as a means to increase self awareness and motivation. But psychodynamic approaches don’t stop there; “why?” is asked of everything, including the patient’s goals, and the symbolic is given equal consideration. Does the patient have the willingness to pause and consider their goals in a broader context? Are they open to taking paths they did not initially expect?

The patient can’t stop eating, so what appetite is he trying to satiate? In what other ways, and in what other areas of his life, might he be starved? What could the food be a substitute for? What fantasies does he have about being thinner or larger? What ideas related to body image has he internalised from his past, his family, and society at large? These questions and many more may float to the surface in the mind of the therapist. 

The “outcome measures” for this kind of qualitative work become more difficult to determine.

Yet another complicating factor is that “clinically significant improvement” isn’t the only goal of CBT. One of the primary goals of CBT, and a strength it has over medication, is that it is supposed to equip the patient with skills and know-how that they can take with them for the rest of their lives. They should ideally leave treatment with enough competence in cognitive behavioural approaches that they could effectively apply these principles by themselves once therapy is over. An adequate level of competency is supposed to enable the patient to continue making gains and manage potential relapses.

A patient might experience clinically significant improvement in treatment when they are being guided by a therapist. But is this the same thing as being taught the principles of CBT to a high enough standard that post treatment, the patient is confidently able to apply theory and techniques to a variety of potential set-backs and challenges?

I hope I have demonstrated to you why the issue of treatment dosage is complex.

My experience has been that people offered the 4 to 8 session model widely seen in community and educational settings often leave feeling like they have only scratched the surface of the presenting issue, especially when that issue has been long-standing. It’s also questionable that patients are receiving the “evidence based treatment” of CBT when many of the problem specific competencies CBT practitioners are taught could not realistically be implemented in their entirety in 4 to 8 sessions. I say this without denigrating the important support work done using very short-term models of counselling and psychotherapy, particularly with those in crisis or acute distress.

I thought carefully about how I wanted to position myself as a therapist in private practice. Given my experience and skill set, I’ve priced myself at the lower end of the scale. I did this because patients are more often under-treated than over-treated, and I want to encourage the people who work with me to give their therapy its rightful time.

As stated previously, therapy duration is unique to each case. In general, most people who enter therapy see improvement by the 10 to 15 session mark. About 20 sessions would achieve recovery for around 50% of people, with a further 25% of people needing between 20 to 50+ sessions. With recovery as a goal, 15 to 30 sessions appears to be a sweet spot for most people, if we look at averages.

Psychodynamic approaches, that operate beyond the metrics of “clinical improvement” and “symptom reduction”, make giving treatment duration averages challenging. Following convention, a commitment of 25 to 40 sessions is recommended for this kind of short-term depth work [8].

Ultimately, you and your therapist should have a shared understanding of what your aims are for therapy, and the work should include reviews to discuss whether you feel like you are achieving them. These discussions would then inform the treatment length that is right for you.

References

1. “Cost and Time” (British Psychoanalytical Society, 2025)

[https://psychoanalysis.org.uk/what-is-psychoanalysis/cost-and-time] (Accessed: 19 Feb 2025)

2. Abbass, A.A., et al (2014). Short-term psychodynamic psychotherapies for common mental disorders (Review). Cochrane Database of Systematic Reviews [https://pubmed.ncbi.nlm.nih.gov/24984083/]

3. Lambert, M. J., Hansen, N. B., & Finch, A. E. (2001) - Patient-focused research: Using patient outcome data to enhance treatment effects [https://psycnet.apa.org/record/2001-06441-003]

4. Hansen, Nathan B.,Lambert, Michael J.,Forman, Evan M. (2002) - The psychotherapy dose-response effect and its implications for treatment delivery services [https://psycnet.apa.org/buy/2002-18013-010]

5. Lambert, M. (2013) ‘The efficacy and effectiveness of psychotherapy’, in Bergin and Garfield’s Handbook of Psychotherapy and Behavior Change. Wiley. 

6. Blane, D. et al. (2013) Cognitive behavioural therapy: Why primary care should have it all, The British journal of general practice : the journal of the Royal College of General Practitioners. [https://pmc.ncbi.nlm.nih.gov/articles/PMC3553606/]

7. “Types of talking therapy” (NHS, 2022) [https://www.nhs.uk/mental-health/talking-therapies-medicine-treatments/talking-therapies-and-counselling/types-of-talking-therapies/] (Accessed: 19 Feb 2025)

8. “Psychodynamic psychotherapy: Individual psychotherapy” (Derbyshire Healthcare NHS Foundation Trust, 2025) [https://www.derbyshirehealthcareft.nhs.uk/services/psychology-services/psychodynamic-psychotherapy] (Accessed: 19 Feb 2025)