This study is concerned with L3 acquisition in heritage speakers (HSs). The goals are to incorporate HS into L3 acquisition research and investigate the role of language dominance for predicting L3 transfer. The study analyzes global accent in German-Turkish early bilinguals, HSs of Turkish, who acquired English as their L3. Twenty native-speaker judges determined accent strength and accent source in the speech of 18 bilinguals as well as 15 controls (L1 English, L1 German, L1 Turkish) when speaking English. Results show, firstly, that bilinguals are perceived as less accented than L1 Turkish speakers and similar to L1 German speakers. Secondly, unlike L1 controls, there is no uniform accent source for HSs when speaking their L3. These results question the role of age of acquisition, while being generally consistent with the TPM. However, HSs seem to benefit from bilingual experience and structure-based transfer can be overpowered by high proficiency.