Background There are many options and little guiding evidence when choosing suture types with which to close the abdominal wall fascia. This network meta-analysis investigated the effect of suture materials on surgical site infection, hernia, wound dehiscence and sinus/fistula occurrence after abdominal surgery. The aim was to provide clarity on whether previous recommendations on suture choice could be followed with confidence. Methods and methods In February 2017, the Cochrane Central Register of Controlled Trials, Medline, EMBASE and Science Citation Index Expanded were searched for randomised controlled trials investigating the effect of suture choice on these four complications in closing the abdomen. A reference search of identified trials was performed. Prisma guidelines and the Cochrane risk of bias tool were followed in the data extraction and synthesis. Two review authors screened titles and abstracts of trials identified. A random effect model was used for the surgical site infection network based on the deviance information criterion statistics. Results Thirty-one trials were included (11,533 participants). No suture material reached the predetermined 90% probability threshold for determination of ‘best treatment’ for any outcome. Pairwise comparisons largely showed no differences between suture types for all outcomes measured. However, nylon demonstrated a reduction in the occurrence of incisional hernias with respect to two commonly used absorbable sutures: polyglycolic acid (odds ratio, OR 1.91; 95% confidence interval, CI, 1.01–3.63) and polyglyconate (OR 2.18; 95% CI 1.17–4.07). Conclusions No suture type can be considered the ‘best treatment’ for the prevention of surgical site infection, hernia, wound dehiscence and sinus/fistula occurrence.