Aim: To compare in-office (chairside) and at-home (dentist-supervised) vital tooth bleaching techniques in terms of efficacy, longevity, safety, sensitivity, and patient-reported outcomes. Material and Methods: A narrative review of literature was conducted using PubMed, Scopus, and Cochrane Library, including randomized trials, systematic reviews, and meta-analyses published between 2000 and 2025. Studies directly comparing in-office and at-home bleaching with peroxide-based agents were selected. Outcomes included color change, relapse over time, intensity of tooth sensitivity, and adverse effects on enamel or pulp. Emphasis was placed on high-quality evidence from the last five years. Results: Both techniques achieved significant, perceptible whitening. Meta-analyses showed no clinically meaningful difference in bleaching efficacy when protocols were followed. At-home bleaching (10–16% carbamide peroxide) and in-office bleaching (25–40% hydrogen peroxide) produced comparable ΔE and shade guide improvements. Some studies suggested slightly greater long-term color stability with at-home bleaching, likely due to longer contact time and ease of touch-ups. Sensitivity occurred frequently with both methods (incidence 37–90% at-home, 17–100% in-office), but was more intense in-office and milder but more recurrent at home. No irreversible pulp or enamel damage was reported. Light activation did not enhance outcomes or reduce sensitivity. Both methods were well accepted by patients. Conclusions: In-office and at-home bleaching are equally effective and safe. In-office offers faster results but higher risk of acute sensitivity; at-home provides gradual whitening with lower intensity side effects and better long-term maintainability. Technique choice should be individualized based on sensitivity profile, desired speed, compliance potential, and lifestyle.