Denny's does not offer printable coupons for Sunday brunch. Printable coupons are available for Denny's for certain meal programs or percentages off, but as of July 2015, it does not have a printable coupon for Sunday brunch.
Each Denny's is independently owned and operated as a franchise, so pricing and coupon acceptance policies can vary from restaurant to restaurant. It is always a good idea to check with any given Denny's location before attempting to redeem a coupon.
Denny's has also initiated a loyalty program that gives members access to exclusive discounts and coupons. Details of that program are available at Dennys.com.