If a company offers you too low a salary for your work, cite financial difficulties as your reason for departure with this printable resignation letter.
Dear Mr./Ms. Bossname
This notice is to let you know that I must respectfully resign my position here at (company), effective (date).
It has been my pleasure to work for (company) over the last (amount of time). However, due to unforeseen financial circumstances coupled with my current salary, I am unable to meet my basic living expenses. Therefore, I must seek employment elsewhere.
I appreciate all that this company has offered me and I wish you the best of luck in the future.