Evidence shows that a degree of overlap is detected between gastroesophageal reflux disease (GERD) and irritable bowel syndrome (IBS). In this review, we aim to update the current evidence from recent studies published in the last decade. Electronic and manual search strategies were both conducted to look for studies that reported the association between gastroesophageal reflux disease and IBS from 2011 to January 2021. We have included all study designs to formulate updated evidence and report all the potential outcome measures. We included a total of 16 studies on a total of 146,156 patients, collectively. Out of these studies, 14 were cross-sectional while only two were randomized controlled trials. The frequency of overlap was hugely variable among the results of the included studies, ranging between 1.7 and 74.7%. Almost all studies used the Rome III criteria for IBS and used questionnaire-based assessment for gastroesophageal reflux disease patients. Female gender and cigarette smoking were the commonest most significant risk factors for developing the overlap. Intestinal hypersensitivity, hyperactive gastric acids, and generalized abnormal motility of the digestive tract were the commonest theories. Obtained evidence remains strong, indicating the overlap between IBS and gastroesophageal reflux disease patients, however, the definite explanation remains non-clear and further studies are needed.