How to write apologyletter for not replying mail

Here's a sample apology letter for not replying to a mail:

[Your Name] [Your Address] [City, State, ZIP] [Email Address] [Date]

[Recipient's Name] [Recipient's Address] [City, State, ZIP]

Dear [Recipient's Name],

I am writing to apologize for not responding to your email dated [Date of Email]. I understand that you took the time to reach out to me and I am truly sorry for not acknowledging your message in a timely manner.

Unfortunately, I have been overwhelmed with work and personal commitments, which has led to a delay in my response. Please know that your email was not ignored, and I have been meaning to get back to you as soon as possible.

I want to assure you that I value our relationship and appreciate your interest in [topic/issue]. I am committed to responding to your email and would like to discuss [topic/issue] further. If you would like, I can schedule a call or meeting to catch up and address any questions or concerns you may have.

Once again, I apologize for the delay and any inconvenience it may have caused. Please know that I am committed to being more responsive in the future.

Thank you for your understanding and I look forward to hearing back from you soon.

Sincerely,

[Your Name]

Alternatively, you can also use a shorter version of the apology letter:

Dear [Recipient's Name],

I am writing to apologize for not responding to your email dated [Date of Email]. I have been overwhelmed with work and personal commitments, which has led to a delay in my response. Please know that your email was not ignored, and I will make sure to get back to you as soon as possible.

Thank you for your understanding.

Sincerely,

[Your Name]

Remember to customize the letter to fit your specific situation and relationship with the recipient.