If you send the letter as an email message the Subject Line of your message should include your name and the reason you are writing i.e. Your Name - Job Offer.
Counter Offer Letter Example
Dear Mr. Bunuel,
I truly appreciate your offer of the position of Head Chef at your premier restaurant "Chez Bunuel" in Manhattan, New York. The opportunity to work in such an exclusive kitchen with a hand picked staff is very enticing for any Chef.
Before I make a final decision, I would like the opportunity to meet with you regarding the salary you have offered. A move to New York City would mean a major commitment, and the compensation would need to be mutually appropriate.
My reputation and creativity are well known throughout the industry, and I would truly appreciate your consideration and discussion in this matter.
Respectfully yours,
Luis Plauten
How to Accept a Job Offer
Tips on the best way to accept a job.

