A notice to vacate is a formal declaration that someone is expected to leave a residence. Landlords typically file a notice to vacate when a tenant has violated the terms of a lease, or when the lease will not be extended. Most landlords file a 30 day notice, and the notice to vacate may be the first step in the eviction process. When landlords file a notice to vacate, they usually hope that the tenants will comply, as evictions are time consuming and expensive, in addition to being irritating to deal with. In the notice to vacate, the reason for the request should be clearly cited.