In November 2023, we published Version 3 of our psychotherapy analysis. This was a working report in which we estimated the effects of psychotherapy in low- and middle-income countries, as well as the cost-effectiveness of two psychotherapy charities: StrongMinds and Friendship Bench. In the first part of 2024, we have updated several parts of the analysis. This present, interim report, Version 3.5, describes the changes we have made so far. Our analysis suggests that both StrongMinds and Friendship Bench are among the most cost-effective charities we have evaluated to date. Friendship Bench has a cost-effectiveness of 53 WELLBYs per $1,000 donated and StrongMinds has a cost-effectiveness of 47 WELLBYs per $1,000 donated.