Having a tenant who's behind on her rent payments is frustrating and worrisome. If she doesn't pay, you might not be able to pay your own bills on time, or perhaps at all. If the situation continues, you might have to deal with the possibility of a costly and time-consuming eviction. Address a tenant who is late with her rent immediately so you can decide on your next steps.
Contact the tenant by phone or in person to ask for back rent if you feel comfortable doing so and your tenant has a good history. She may have a temporary financial problem or other issue preventing her from paying rent in full. Work out a solution to have the back rent paid in full if possible.
Review the tenant's lease and state and local laws regarding late rent if you don't want to ask her informally. Follow any specific steps required by law or your lease to officially notify tenants of owed rent. For example, in Illinois, you have to give your tenant five days to pay after the day you gave her a past due notice before starting any eviction proceedings. The notice has to include her name, the rental description, the total due and the date she has to pay it by. Illinois law requires you be open and available to receive rent for the five days, so you can't include days you're not available in the total.
Place the request for back rent payment in writing. You'll need to date the notice, identify your tenant and the rental property in it and sign it. Include the total amount due plus late fees you're allowed to charge under law and the lease terms. Itemize the amounts to show how you got your total. For example, Mark's rent is $600 each month and his lease allows for one $50 late fee for each month he is late past the 15th of the month. Mark owes his landlord June and July in back rent. His landlord breaks it down by showing $600 for June, $50 for June's late fee, $600 for July and $50 for July's late fee, for a total of $1300.
Deliver the written request for back rent to the tenant. Make a copy for yourself. Send the request by certified mail, with return receipt requested. That way you have proof you sent the letter if you have to go to court. Keep the return receipt with the notice copy.