BACKGROUND The European association for the study of the liver and chronic liver failure consortium (EASL-CLIF) recently proposed diagnostic criteria for acute on chronic liver failure (ACLF). There is lack of data regarding liver transplant outcomes in ACLF patients based on these criteria. The objective of this study was to determine outcome following living donor liver transplantation (LDLT) in ACLF patients. METHODS We retrospectively reviewed patients who underwent LDLT for ACLF based on European association for the study of the liver and chronic liver failure consortium (EASL-CLIF) diagnostic criteria (group 1) (N = 60) and compared them with ACLF patients who did not undergo transplantation (group 2) (N = 59). The primary outcome of interest was 30 day mortality. We also looked at one year survival in these patients. Survival was calculated using Kaplan-Meier curves and Log rank test was used to determine significance between variables. RESULTS Median MELD scores for group 1 and 2 patients in ACLF grade 1 was 28 (20-38) and 31 (24-36), in ACLF grade 2 was 35 (24-42) and 36 (24-42) and in ACLF grade 3 was 36 (29-42) and 38 (32-52). For group 1 and 2, 30 day mortality in ACLF grade 1, 2 and 3 was 2/43(4.6%) versus 9/15(60%) (P < 0.001), 1/15 (6.6%) versus 13/19 (68.4%), 0/2 (0%) versus 20/25 (80%) (P < 0.001). Actuarial 1 year overall survival was 92% versus 11% (P < 0.001) in patients who underwent transplantation versus those who did not. One year survival in patients with grade 1 and 2 ACLF who received transplant versus medical treatment was 91% versus 13% and 93% versus 15% (P < 0.001) respectively. CONCLUSIONS LDLT has excellent outcomes in patients with EASL-CLIF grade 1 and 2 ACLF. Without transplantation, ACLF patients have a very poor prognosis.