We report outcomes of 17 children with brachial plexus birth palsy that underwent extensor carpi ulnaris to brachioradialis and brachioradialis to abductor pollicis longus transfers to correct supination and ulnar deviation deformity. Mean age at the time of surgery was 8.7 years and mean follow-up time was 21 months (8-44). These patients had marked increases in active forearm rotation and Canadian Occupational Performance Measure scores. Activity performance score on the measure increased from 1.1 to 6.7 and satisfaction score increased from 0.8 to 8.7 at final follow-up. We conclude from our patient series that these tendon transfers are effective in correction of the supination and ulnar deviation deformities in brachial plexus birth palsy.