In L2 Chinese vocabulary instruction, the most conventional method of teaching is to present the new character, its English translation, and pinyin as a pronunciation guide to the segmental and tonal information. In this study focusing on tone formats and the presence of a phonetic radical, we investigated how these two aspects could impact tone acquisition. In the experiment, L2 Chinese participants of three proficiency levels learned 24 unfamiliar words, passed a criterion test with 90 % correctness, and completed a tone perception and production task. The results showed that the learners perceived and produced tones significantly better when characters were shown with tone diacritics and when the phonetic radical was reliable. The presence of pinyin with tone number did not facilitate tone acquisition more than the condition where pinyin was unavailable. The learners’ proficiency levels, only affecting the number of learning sessions required to pass the criterion test, did not correlate with their tone performance.