Decamethylcyclopentasiloxane (D5) is a high-production-volume chemical that is emitted to air in tens of thousands of tonnes each year globally. However, specific information about emission rates to air is still limited. Here we present an estimate of D5 emissions from the city of Chicago based on measurements that have recently been published. We used a multimedia environmental fate model parameterized for Chicago to back-calculate the emission rate of D5 from the measurements. Our estimated average emission rate for D5 is 500 (2.5-to-97.5-percentile interval: 260-1100) kg d(-1). The corresponding per-capita emissions of 190 (100-420) mg capita(-1)d(-1) agree well with previous estimates for Europe and North America.