A business that leases real estate and improvements (buildings, etc.) in the form of space for offices, a warehouse, a restaurant, a nail or hair salon, a clothing store, a coffee shop, or other commercial (nonresidential) space will usually be required to sign a written contract known as a commercial lease agreement.

If the tenant (the business occupying the space) who signs a commercial lease agreement fails to pay the rent on time, the landlord may have the right to charge late fees, terminate the lease, and lock the commercial tenant out of the space by changing the locks.

A commercial landlord’s ability to charge late fees generally depends on the specific language in the written lease agreement and the state's contract law.

Contract law in most states recognizes an implied duty of good faith and fair dealing between parties to a contract, and a commercial landlord who charges late fees because the tenant is an hour late paying the rent may be in breach of the landlord’s implied duty of good faith and fair dealing—unless, for example, the lease agreement specifies an hour (12:00 p.m.) of the day by which rent is due and states that time is of the essence.

In Kansas, a business leasing commercial space such as offices, warehouses, or retail locations will typically enter into a commercial lease agreement. This contract outlines the terms of the lease, including rent payments, the use of the property, and the responsibilities of both the landlord and the tenant. If a tenant fails to pay rent on time, the landlord's right to charge late fees, terminate the lease, or lock the tenant out depends on the terms of the lease agreement. Kansas contract law, like that in many states, includes an implied duty of good faith and fair dealing in contractual relationships. This means that a landlord's actions, such as charging late fees or locking out a tenant, must be reasonable and in line with the lease's provisions. For instance, a landlord may be justified in charging late fees or taking action if the lease specifies a precise time by which rent is due and emphasizes that timely payment is critical ('time is of the essence'). However, actions perceived as overly harsh or unreasonable given the circumstances may be challenged as a breach of the implied duty of good faith and fair dealing.