__________(Name of the Company),
__________(Name of the Employee),
Subject: Thank you letter
With due respect, my name is __________(Name), __________(Designation) from department __________(Department).
I am writing this to thank you, for your support in __________ (Mention how your boss supported you). From the time I started this job, you have been very helpful and supportive and this gesture means a lot to me. I appreciate the time I spent working for you, on both the professional and personal front.
I highly appreciate all your efforts and I promise I will maintain my performance throughout my time in this company and will never let you down.