Tenant giving 30 day notice.

[Rhonda Healey]

We are new to this and actually started as a fluke. We bought a house in a different area before we even listed our house. Long story short we had the opportunity to rent our house during slow winter months and now own 3 rentals!! Our first renters were month to month as we didn't know what our plans were and then decided to move after 5 months. My question is, they have 30 days notice in middle of month, do we need to prorate the next month or do they pay a full month even though they vacated in middle of month? What are the thoughts on this?