Hi [Recruiter Name],
Thank you so much for offering me the [Role Title] internship at [Company Name]. It has been a pleasure speaking with you and the team and learning more about the company.
Unfortunately, after giving a great deal of thought to this career opportunity, I have decided that it is in my best interest, as well as the company’s, to turn down your gracious job offer. I have recently decided to accept another position that I believe is a better fit for my abilities and skill set. I am so sorry for any inconvenience my decision may cause.
I continue to be impressed with [Company Name]'s impact on [Insert something related to mission, values, or current events], and particularly with the support you provided throughout the recruitment process.
I wish you all the best in your future endeavors and I hope to stay connected!
Sincerely,
[Your Name]