No, Sonic Electronix only allows one promo code per order. If you try to enter a second code, the checkout system will replace the previous code or display a message like “Only one promo code can be applied per order.” Key details: - You can combine a promo code with sitewide sales or automatic discounts, but not with another code. - Some codes (like student or military discounts) may require verification and cannot be stacked with other offers. - The checkout page will always show which code is active and let you remove or replace it. Pro tip: Compare available codes before checkout and use