When the clinical manifestations of colovesical fistulae lack diagnostic features, significant diagnostic delay may result. The literature contains conflicting recommendations regarding the optimal method of imaging such fistulae. We describe the transabdominal ultrasound appearances of a colovesical fistula and review the relevant literature. The identification of the ureteric orifices with their associated urinary jets and the use of abdominal compression are essential components of the technique.