As a custom flag maker, we can make your custom pennant flags in any size! Therefore, we don’t really have any standard sizes. All you have to do is tell us what size you want, and we’ll make it happen. If you aren’t sure what size to order, let us know what you’ll be using the pennants for, and we can provide you with a professional recommendation. For example, polyester pennants that will be used on a boat are generally 12 inches by 18 inches. If you plan to use the pennant on a home or a business, we would recommend a larger size of 3 feet by 5 feet.