Dear [Recipient's Name], I hope this letter finds you in good health. I am writing to sincerely apologize for missing the deadline for [project/task] that was due on [deadline date]. I understand the importance of adhering to timelines and the inconvenience this may have caused to both you and the team. Furthermore, I take full responsibility for my oversight and assure you that it was not intentional. [If applicable, provide a valid reason for missing the deadline. For example, if there were unexpected circumstances beyond your control, briefly explain them.] I deeply regret any inconvenience caused and understand that my delay may have disrupted the workflow or impacted subsequent tasks. I assure you that I have taken immediate steps to rectify the situation and prioritize completing the project as soon as possible. To prevent any further delays, I have reassessed my workload and reprioritized my tasks accordingly. I have also put measures in place to ensure better time management and avoid similar situations in the future. I understand the importance of this project and the value it holds for both our team and the company. Furthermore, I acknowledge the trust you have placed in me to deliver on time, and I sincerely apologize for failing to meet your expectations. Moving forward, I am committed to completing the project within the revised timeline of [provide new deadline, if applicable]. I will make sure that the quality of work is not compromised in any way, and I am more than willing to put in additional hours to ensure its successful completion. Once again, I deeply apologize for the inconvenience and assure you that I have learned from this experience. I value our working relationship and assure you that such an oversight will not be repeated. I am always available to discuss any concerns or suggestions you may have regarding the project or its timeline. Thank you for your understanding and giving me the opportunity to rectify my mistake. I look forward to delivering the project promptly. Yours sincerely, [Your Name] [Your Contact Information]