Architecture and Design both are based on a creative process. Sketches can be a useful tool for designers through the complex process of anticipating a project. A colorful sketch can more easily study and communicate because the use of color provides important visual definitions. For designers, using color can be advantageous for representing and differentiating several materials, as well as comparing several possibilities, for the final colors choice for a specific product, for a building or interior design, for a graphic communication or a web design. Furthermore, in the last decades, sketching became popular through the so called Urban Sketchers. The practice of hand drawing on site, through the observation and recording of buildings and monuments in historic city centers can lead to knowledge, belonging and appreciation of heritage. The recent NEB principles encompass: rediscovering a sense of belonging. The Urban Sketchers practice can help to revisit our cultural heritage, supporting knowledge and leading to the feeling of being part of and integrating into the local social and cultural context. In this kind of sketches, color is relevant to call out important information about buildings and monuments, and can guide the eye through the urban space. Under a qualitative research, based on a literature review methodology, through the study and interpretation of several authors, and based on the analysis of sketches using color produced by architects, designers and urban sketchers, this paper investigates the importance of color use, aiming to stimulate reflection and bringing new perspectives on color relevance in sketches.