Zip Code 75070 Core Based Statistical Area. 75070 is located in the state of Texas in the Dallas-Fort Worth metro area. Zip code 75070 is primarily located in Collin County. The official postal service name used for 75070 is MCKINNEY, Texas. Portions of the 75070 zip code are contained within or border the city limits of McKinney, TX, Frisco, TX, Fairview, TX, and Allen, TX. Zip code 75070 is part of area code 214, area code 469 and area code 972.