Circle K at 3700 Elm St, St Charles, MO, US is a convenience store and gas station offering a wide variety of products for people on the go. If you are looking for a great cup of coffee, a cold beverage, a Polar Pop cup or a Froster drink, or fresh food to go, we are the place to visit. We have premium quality fuels and an excellent car wash. Our fast and friendly team is always happy to serve you!