We assessed the impact of an HIV/AIDS programme for Nepalese migrants to India that involved writing letters. The programme created opportunities for sending HIV/AIDS-related messages to the migrants in India, and encouraging them practicing safer sex. Initially, they received the messages only from the programme, but later from their colleagues, spouses or other family members. They discussed the messages in groups, disseminated them, and sought more knowledge in their destinations. These findings indicated that using letters could be an effective way to reach inaccessible migrants at their destinations, and help them to improve their HIV/AIDS-related knowledge, and safer sex practices.