During checkout, look for the "Apply Coupon Code" link to enter in a coupon code before confirming your reservation. This field is located on the payment page, to the right of your credit card information.
You can only apply one coupon code per reservation. Coupons cannot be used over multiple reservations. If the coupon amount is more than the total reservation amount, the remainder of the coupon's value is forfeited and cannot be transferred to another reservation. Unfortunately, coupons cannot be retroactively applied.
Unfortunately, DogVacay can not retroactively apply coupon codes. Some coupon codes are for "first booking only" or "first-time customers only". These codes can only be used by guests who do not have any previous Reservation Requests (or Custom Quotes) with DogVacay.