Send this letter to a potential employer after you have been offered a job, but would like to reject the offer.
{Date}
To: {Name}
{Address}
{City, State, Zip}
Dear {Recipient},
I am extremely flattered to be offered the {name of position} position at {name of company}. I enjoyed meeting with you in the interview, and I liked the atmosphere of the company.
I'm afraid I will have to decline the offer, though. Upon further reflection, I've come to the realization that this position just isn't right for me, largely due to the fact that {reasons you can't take the job}.
Again, thank you for taking the time to meet with me. Perhaps another position will come available that will be better suited for my skills. If that happens, I hope you will keep me in mind.
Sincerely,
{Sender}