One tenant moving out. What to do with last months rent?

[Matt Nolan]

Hello Bigger Pockets,

I have a rental property in Watertown MA, and the lease is expiring soon.  I sent out a lease renewal letter and I just heard back from the tenants this afternoon.  

The rental has three tenants consisting of a couple (boyfriend/girlfriend) and a mutual friend.  I was informed today that the friend would no longer be living at the rental and will be moving in with her boyfriend.

My question is this: How do I go about separating/refunding last months rent?  I currently have an account dedicated to last months rent ($1,850).  Do I refund the $1,850 to the three of them and have the remaining couple cut a new check?  Do I have the couple cut me an additional check for the new outstanding balance ($616.67)?  Is there another option I'm missing entirely?

I would think this is a fairly common occurrence, so I'm looking to the collective wisdom of BP to set me on the right track.

Thanks in advance,

-  Matt Nolan

[Kim Meredith Hampton]

@Matt Nolan do a roommate lease form having the tenant leaving sign that he is in fact vacating and understands that the deposit remains with the unit. The other two sign the document as well. The deposit always remains with the property until all tenants have vacated. They must work out the money amongst themselves, not your problem