The Colorado lease termination letter is official notice that is given from a landlord to tenant in order to inform them to vacate the property. The specific amount of notice depends on how long the tenant has been on property in accordance with § 13-40-107 (see table below):
| Tenancy Period | Required Notice |
| 1 year or longer | 91 days |
| 6 months or longer but less than 1 year | 28 days |
| 1 month or longer but less than 6 months | 21 days |
| 1 week or longer but less than 1 month | 3 days |
| 1 day but less than 1 week | 1 day |
Laws – § 13-40-107
