This otherwise-positive resignation letter makes it clear that pay inequities led to the employee giving notice. It includes an offer to give feedback to management on the issue.
Dear Mr./Ms. Bossname,
This letter shall serve as two weeks’ notice of my resignation.
It was only due to recent national trends toward salary transparency, and federal laws forbidding employers from punishing employees for discussing their pay, that the stark inequities at this company came to light. Specifically, I learned that despite significant differences in our skills sets and length of employment, I am being paid more than 30 percent less than new hires.
I appreciate the opportunities afforded me by this company, including several promotions and awards over the years. I only regret that I did not also experience salary growth commiserate with my experience and expertise.
I would be happy to talk with management or human resources if they are open to feedback on this issue.