Superiors and coworkers can use this professional goodbye letter to congratulate an employee on their retirement.
Dear {Recipient},
I'm so sad that you are retiring, but so happy that you'll get to spend more time {favorite activity or person to spend with}. You really deserve to have a wonderful retirement after all the hard work you've put in.
Remember how you taught me to {work-related story}? I'll always be grateful for the time and energy you put into keeping me on my toes at work. Everyone at {company} really admires your commitment to excellence.
Even though I won't be seeing you as often, I'd still like to keep in touch. Perhaps once you get into the swing of retirement we can {activity}?
I'm sure we'll talk soon.
Best wishes,
{Sender}
