Abstract Background and study aims Biliary strictures are a major cause of morbidity following liver transplantation. In the present prospective comparative trial, we evaluated balloon dilation vs. balloon dilation plus stenting with regard to technical and clinical efficacy as well as complications. Patients and methods A total of 32 patients with symptomatic biliary strictures after liver transplantation were assigned to balloon dilation (n = 17) or balloon dilation plus plastic stent placement (n = 15). The main outcome parameter was sustained clinical success defined as an interval of at least 3 months without further endoscopic intervention. Additional outcome parameters were assisted clinical success and treatment failure, as well as procedure-related complications. Results The initial technical success and primary clinical success rates in the dilation group were both 100 %; in the stent group, the corresponding rates were 100 % and 93 % (n.s.). The sustained clinical success was 71 % vs. 73 %, respectively (n. s.). The time interval to reach sustained clinical success was 6.1 and 5.1 months, respectively (n. s.). No significant differences were found in assisted clinical success or in treatment failure. Complications were observed in 4.3 % in the dilation group and 13.6 % in the stent group (P < 0.05). Independent of the treatment group, a sustained clinical success in anastomotic strictures was achieved in 100 %, whereas the success rate of strictures of the donor hepatic duct was 50 % and of strictures involving the hilum, only 14 % (P < 0.05). Conclusions In patients with biliary strictures after liver transplantation, endoscopic balloon dilation alone was as effective as dilation plus stent placement. Stent placement was associated with a significantly higher complication rate. Endoscopic treatment of strictures of the biliary anastomosis is highly effective, whereas attempts to treat more complex strictures are less promising.