"Please accept my heartfelt condolences," "My heart and prayers are with you during this difficult time," or "Wishing you peace." Another thing to remember when writing a letter of sympathy is to focus on what the person is going through.Make sure you include the name of the person who died or mention the specific incident that caused sorrow for the person. To answer your question directly, I'm very sorry for your loss, would be the most usual subject line. Dear Claimant: Please accept our condolences on your recent loss.