For years, the gold standard for Ulcerative Colitis (UC) remission was mucosal appearance during endoscopy. However, recent literature suggests histological or “deep” remission is important for preventing flares and maintaining clinical remission. There are now validated histological scoring systems to identify subclinical inflammation, the simplest being the Nancy Histology Index (NHI). Colonoscopy with histological evaluation is the gold standard for UC monitoring, but frequent endoscopy is not always possible.