If the tenant were to pay all of the rent they owe, plus the costs of filing, and possibly even the Sheriff’s fees, then the tenant would void the eviction notice, and could stay in the unit. In that case, a landlord cannot assume that the tenant is definitely leaving.

If the payment is not made, then the landlord must apply to the sheriff for enforcement of the order unless the tenant has clearly moved out.

If you are 100% sure that the tenant has moved out, then you do not have to file with the Sheriff’s office. The problem for most landlords is that they cannot know for certain that the tenant is gone, so you should “err on the side of caution” when coming to the conclusion about whether or not the tenant still resides in the unit. It just helps to avoid being fined by the Board, or being taken to the Board by the tenant for illegal entry, if they were still living there.