Studies on object and word naming have shown that the age at which words are acquired is an important factor in processing times. Research on the issue in Dutch has been hampered by the fact that only teacher ratings were available about which words should be known by 6-year-olds. As a supplement to these teacher ratings, we conducted a large-scale study in which 558 students rated the age-of-acquisition of 2816 four- and five-letter nouns. Reliability of the ratings is high, and correlations with word frequency and word imageability are in the same order as those reported for English.