Mindfulness-based Cognitive Therapy (MBCT) was not intended for current depression, and lengthy mindfulness practices (≥30 min) can be challenging. Person-based cognitive therapy (PBCT) includes brief mindfulness practices (<10 min). While group PBCT can improve depressive symptoms whether benefits can be attributed to the brief practices is unclear. Twenty-eight participants with chronic major depression were randomly assigned to PBCT (n = 14) or treatment as usual (n = 14). Measures of mindfulness and depression were taken. Six PBCT participants were interviewed. Improvements in mindfulness in mediating the relationship between group and improvements in depressive symptoms just failed to reach statistical significance (95% confidence interval −0.97 to 14.84). Thematic analysis identified four themes: ‘altered relationship to symptoms’, ‘impact on self’, ‘the challenge of letting go’ and ‘effect of the group’. Although bootstrapped indirect effects were in the hypothesized direction they failed to reach statistical significance; this could be due to low power, but further research is needed. Qualitative themes support the potential of brief mindfulness practices and are similar to themes identified of mindfulness-based interventions with lengthier mindfulness practices. Findings suggest that some people experiencing current depression report benefit from the brief mindfulness practices included in PBCT but further research in larger samples is now needed.