For example, if you move into a new apartment, you can sign the lease in advance. Often, landlords and tenants sign the contract weeks or sometimes months in advance. While you can sign the lease well in advance of the official entry into your new building, you will not be subject to the terms of your lease until after the effective date. For most leases, this is the first day of your fixed-term or auto-renewing lease agreement. This is also often the day when you can get and collect the keys. This means that even if you signed your lease months before you move in, you don`t have to keep the unit clean, pay rent, or anything else until your lease actually starts (unless something else in your contract provides for something else). Conversely, you also cannot live on the site until the effective date.