Memory cells having heaters with angled sidewalls and methods of forming the same are described herein. As an example, a method of forming an array of resistive memory cells can include forming a first resistive memory cell having a first heater element angled with respect to a vertical plane, forming a second resistive memory cell adjacent to the first resistive memory cell and having a second heater element angled with respect to the vertical plane and toward the first heater, and forming a third resistive memory cell adjacent to the first resistive memory cell and having a third heater element angled with respect to the vertical plane and away from the first heater element.