[Your letterhead, if desired; if not, your return address]
[Date of letter—month, day, and year]
[Recipient's first and last names]
[Street or P.O. box address]
[City, State ZIP code]
Dear [recipient's name]:
I am writing to tell you how sorry I am for stealing your bottle of perfume. I was obviously wrong to do this, and I know how upset you were over this happening. I want to return the perfume to you as soon as possible, so please let me know when and where we can arrange to do this. I know this does not make up for the mistake I made, but I want to also buy you a new bottle of the perfume. So please let me know where I can purchase this.
Again, I apologize for doing this, and I hope you will forgive me for making such a terrible mistake.
[Sender's first and last names]