Multiple genetic variants have been associated with adult obesity and a few with severe obesity in childhood; however, less progress has been made to establish genetic influences on common early-onset obesity. We performed a North American-Australian-European collaborative meta-analysis of fourteen studies consisting of 5,530 cases (≥95^th percentile of body mass index (BMI)) and 8,318 controls (<50^th percentile of BMI) of European ancestry. Taking forward the eight novel signals yielding association with P < 5×10⁻⁶ in to nine independent datasets (n = 2,818 cases and 4,083 controls) we observed two loci that yielded a genome wide significant combined P-value, namely near OLFM4 on 13q14 (rs9568856; P=1.82×10⁻⁹; OR=1.22) and within HOXB5 on 17q21 (rs9299; P=3.54×10⁻⁹; OR=1.14). Both loci continued to show association when including two extreme childhood obesity cohorts (n = 2,214 cases and 2,674 controls). Finally, these two loci yielded directionally consistent associations in the GIANT meta-analysis of adult BMI¹.