Monitor is a small unincorporated community in Chelan County, Washington, United States. It is situated along the Wenatchee River about 8 miles upstream from its junction with the Columbia River in the fertile Wenatchee Valley. Monitor is part of the Wenatchee–East Wenatchee Metropolitan Statistical Area. The USPS ZIP Code for Monitor is 98836. According to data from the 2000 census, the total population in the Monitor ZIP code was 342 persons.