Background Psychological morbidity and reduced quality of life are common and linked with nonadherence to medication in psoriasis. Access to psychological therapy is often poor with long waiting times. Cognitive behavioural therapy (CBT) is a well-accepted therapy for psychological disorders and is particularly effective when tailored to address condition-specific concerns. Objectives To determine whether an electronic CBT intervention for Psoriasis (eTIPs) would reduce distress, improve quality of life and clinical severity in patients with psoriasis. Methods This was a wait-list, randomized trial of immediate intervention vs. usual care. Self-assessed psoriasis severity (Self-Administered Psoriasis Area and Severity Index), distress (Hospital Anxiety and Depression Scale) and quality of life (Dermatology Life Quality Index) were measured before and after intervention. Analysis was based on complete cases and all cases using multiple imputation to substitute missing values. Results Anxiety scores between groups were significantly reduced (P <0·05) for complete cases only; the mean (SD) scores were: intervention 7·6 (3·6) at baseline and 6·1 (3·5) at follow-up vs. control 8·3 (3·5) at baseline and after intervention 8·1 (4·4) (P = 0·004). Depression scores did not change; the experimental group scores at baseline were 5·0 (4·2) and after intervention 4·0 (3·7) vs. control group at baseline 5·2 (3·4) and after intervention 4·9 (3·8). Psoriasis severity scores did not change: baseline scores for the experimental group were 7·5 (6·0) and after intervention 6·5 (8·5) vs. the control group before 8·3 (6·3) and after 7·6 (6·1) (not significant). Quality-of-life scores improved in both analyses (P <0·05); the intervention group scores before were 6·6 (4·2) and after intervention 5·0 (5·1) vs. control before 7·4 (4·4) and after intervention 7·7 (4·5) (P = 0·042). Conclusions This first online CBT intervention for people with skin disease showed improvement in anxiety and quality of life in patients with psoriasis. The results are limited by the large amount of missing data and, at this stage, online delivery cannot substitute for established methods of delivery for CBT. What's already known about this topic? Psychological morbidity and distress are common in psoriasis. Cognitive behavioural therapy (CBT) is effective for patients suffering psychological problems associated with chronic plaque psoriasis. Web-based psychological programmes for other patient groups are an acceptable alternative to face-to-face interventions. What does this study add? A novel, tailored, web-based form of CBT for patients with chronic plaque psoriasis shows benefits in anxiety reduction and quality-of-life improvement These findings from online delivery of CBT, although less impressive than with face-to-face CBT delivery in psoriasis, may help to overcome problems of access to psychological therapy. © 2013 The Authors BJD © 2013 British Association of Dermatologists.