Living in a rented property can be a good experience, or it can be very bad. You hear all sorts of stories about bed bug infested dwellings, so it is useful to know where you stand.
The thing to remember when manoeuvring through the often shaky tenant-landlord relationship is that your lease (or other binding statement) should be your point of reference when trying to win any battle. Same thing goes for dealing with pest infestations. Here are some general rules of thumb, however, in terms of knowing who is usually responsible for pest removal in rental situations.
At the time of rental
Generally speaking, the landlord is responsible for paying for (and completing) removal of any kind of pest that is present before or at the time of the tenant moving into the rented property. It’s simple, really. The landlord is responsible in these situations because the property belongs to her/him. 
After the tenancy is in place
The tenant, then, is typically responsible for paying for and completing any pest problem that comes into the rented space after moving in. It may seem unfair, but this is why tenants should make sure there are no infestations before moving in. “Pick over it with a fine-tooth comb”, as the saying goes.
Keep in mind that pests are often brought into a rented home because of the tenant’s lifestyle, so it is unfair to hold landlords responsible after the lease has been signed, for that reason.
These tips should serve as a general guide for learning how to things usually work with your landlord, but you should always refer to the rental agreement if you are uncertain, or, simply ask the landlord him/herself. The tenant doesn’t have to pay a lot of money for pest removal with a good, cost effective pest control company, and there are lots of tips online available to help tenants out, too!