Introduction HIV self‐testing (HIVST) is a promising strategy to improve diagnosis coverage among key populations (KP). The ATLAS (Auto Test VIH, Libre d'Accéder à la connaissance de son Statut) programme implemented HIVST in three West African countries, distributing over 380,000 kits up between 2019 and 2021, focussing on community‐led distribution by KP to their peers and subsequent secondary distribution to their partners and clients. We aim to evaluate the cost‐effectiveness of community‐led HIVST in Côte d'Ivoire, Mali and Senegal. Methods An HIV transmission dynamics model was adapted and calibrated to country‐specific epidemiological data and used to predict the impact of HIVST. We considered the distribution of HIVST among two KP—female sex workers (FSW), and men who have sex with men (MSM)—and their sexual partners and clients. We compared the cost‐effectiveness of two scenarios against a counterfactual without HIVST over a 20‐year horizon (2019–2039). The ATLAS‐only scenario mimicked the 2‐year implemented ATLAS programme, whereas the ATLAS‐scale‐up scenario achieved 95% coverage of HIVST distribution among FSW and MSM by 2025 onwards. The primary outcome is the number of disability‐adjusted life‐years (DALY) averted. Scenarios were compared using incremental cost‐effectiveness ratios (ICERs). Costing was performed using a healthcare provider's perspective. Costs were discounted at 4%, converted to $USD 2022 and estimated using a cost‐function to accommodate economies of scale. Results The ATLAS‐only scenario was highly cost‐effective over 20 years, even at low willingness‐to‐pay thresholds. The median ICERs were $126 ($88–$210) per DALY averted in Côte d'Ivoire, $92 ($88–$210) in Mali and 27$ ($88–$210) in Senegal. Scaling‐up the ATLAS programme would also be cost‐effective, and substantial epidemiological impacts would be achieved. The ICERs for the scale‐up scenario were $199 ($122–$338) per DALY averted in Côte d'Ivoire, $224 ($118–$415) in Mali and $61 ($18–$128) in Senegal. Conclusions Both the implemented and the potential scale‐up of community‐led HIVST programmes in West Africa, where KP are important to overall transmission dynamics, have the potential to be highly cost‐effective, as compared to a scenario without HIVST. These findings support the scale‐up of community‐led HIVST to reach populations that otherwise may not access conventional testing services.