Hiatal hernia is an underlying factor contributing to gastroesophageal reflux disease (GERD). However, it remains elusive whether the size of the esophageal hiatus has a de facto influence on the lower esophageal sphincter (LES), on the intensity of patient reflux, on GERD symptoms and on the quality of life (QoL). One hundred patients with documented chronic GERD underwent laparoscopic fundoplication. QoL was evaluated before surgery using the Gastrointestinal Quality of Life Index (GIQLI). Additionally, GERD symptoms and nonspecific gastrointestinal symptoms were documented using a standardized questionnaire (score 0-224). The size of the esophageal hiatus was measured during surgery by calculating the hiatal surface area (HSA). Correlation analysis between the preoperative QoL, GERD symptoms, esophageal manometry, multichannel intraluminal impedance monitoring data and HSA size was performed, in order to investigate whether the HSA has an influence on the patients'symptoms, GIQLI, manometry and multichannel intraluminal impedance monitoring data. Statistical significance was set at a P-value of 0.05. The HSA sizes ranged from 1.51cm(2) to 16.09cm(2) (mean 4.14cm(2) ). The preoperative GIQLI ranged from 15 points to 133 points (mean 94.37 points). Symptom scores ranged from 2 points to 192 points (mean 49.84 points). No significant influence of the HSA on GIQLI or preoperative symptoms was recorded. HSA size had a significant negative effect on LES pressure. Additionally, there was a significant positive correlation between HSA size and number of refluxes in supine position. For the rest of the evaluated data, including DeMeester score, total number of refluxes, refluxes in upright position, acid reflux events, proximal reflux events, LES length and body motility, no significant correlation was found. Although patients subjectively are not significantly affected by the size of the hiatus, it has significant effects on the LES pressure and on gastroesopageal reflux in supine position.