Usually, itu2019s defined as u2018calendar daysu2019, so yes, it would include the Sunday in that case. However:There is normally a specific method to notify - and few contracts allow email, as itu2019s not considered reliable. You MUST use one of the methods in the contract.It may be 30 days from acknowledgement, not from notification, and if your landlord does not work the weekends, this would be the Monday at the earliest. Again, check the contract.Your notice may have to be sent on a specific day of the month, usually related to rental payment dates.