Dear [Manager's Name],
Please accept this letter as formal notification of my resignation from my position as [Job Title] at [Company Name]. My last day of employment will be [Month Day, Year], in accordance with the [number]-day notice period required by my employment contract.
I am committed to ensuring a smooth transition and will assist in any way possible during this period.
Thank you for the opportunity to be part of the team.
Sincerely,
[Your Name]
[Date]