BACKGROUND: Randomized, controlled trials (RCTs) have found repetitive transcranial magnetic stimulation (rTMS) to be effective for major depression, but its usefulness as an augmenting strategy for severe treatment-resistant depression (TRD) has yet to be firmly established. METHODS: In a naturalistic trial, 15 chronically depressed, severely treatment-resistant patients were treated with daily high frequency (HF) rTMS over the left dorsolateral prefrontal cortex (DLPFC) for 4 weeks as an augmenting strategy. Depressive and anxious symptoms (both subjective and objective), as well as quality of life (QOL) domains were measured pre-post rTMS treatment. RESULTS: Pre-post rTMS comparisons revealed significant reductions of both clinician-rated and selfreport depression and anxiety measures and increases in three (out of five) domains of subjective QOL (i.e., global, physical, and psychological). LIMITATIONS: Small sample size and non-controlled design. CONCLUSIONS: Our results suggest that HF rTMS, when used as an augmenting strategy, positively affects depressive and anxious symptoms as well as QOL in patients with severe TRD. However, further studies with larger samples and controlled designs are needed to better clarify our preliminary findings.