Dear [Employer],

I am writing to inform you of my intention to resign from my position as [job title] at [Company Name].

I have appreciated my time here, and I thank you for the opportunities and experiences I have gained throughout my employment.

I have decided to pursue a new challenge which unfortunately means I must resign from my current role. My last day of employment will be [date].

If I can be of any assistance during this transition, please do not hesitate to contact me.

Sincerely, 
[Your Name]
Scrivi una lettera di dimissioni.