In recent decades, the need for introducing openings in RC beams has been increasing. Several utility services, such as electrical cables, water pipes, air conditioning, and network connections, require one or more openings for easy bypassing. Web openings significantly affect the service and ultimate stages of RC beams. In the service stage, more excessive deformation is induced by opening presence due to stiffness reduction. Furthermore, high stresses in the ultimate stage result from web openings, especially in the opening region. Openings disturb the stress flow due to the abrupt change in the geometry leading to a stress concentration around the opening. Several researchers have studied different methods in order to compensate for the loss in beam deflection and strength. This paper presents a state-of-the-art review of RC beams with web opening and discusses some proper strengthening techniques. The classifications of openings in RC beams in terms of size, shape, execution time, and direction are discussed. Moreover, RC beams' flexural and shear failure modes due to openings are presented. Several strengthening techniques are discussed in this review study to distinguish their pros and cons. It can be concluded that beams with openings at the flexure span behave better than the shear span. Also, circular openings are preferable among all shapes. Moreover, strengthening RC beams with openings using ferrocement and SHCC significantly enhances the beams' performance. Last, this paper also sheds more light on the importance of considering the opening in the preliminary design stages to avoid unexpected and undesirable failures.