Most syrups store well in a dry location at room temperature. Some syrups can last this way for up to 12 months. However, once you open the bottle, the syrup begins to deteriorate. When you leave a pump on the bottle, the syrup may only last up to a month. If you replace the cap on the bottle after each use, it can last significantly longer. Some sauces that include milk products may require refrigeration after opening. Check the label of your coffee syrup for specific storage instructions.