The present work investigated the outdoor performance of a basin type multi-stage solar still as well as the effect of collector over basin area (CBA) ratio on the distillate production. The effect of CBA was studied in outdoor experiments for the first time. The system consisted of a still coupled with one, two or three flat-plate solar collectors. In order to study the effect of CBA more accurately, the experiments were conducted in both winter and summer. In these experiments, the distilled water production of the multistage still was measured during the whole 24 h of a day on an hourly basis. The results revealed that in the winter, the basin coupled to one solar collector (CBA = 3.45) produced 11.56 kg of distillate. Adding a second collector (CBA = 6.90) to the system increased the production by 96%, whereas adding a third one (CBA = 10.35) increased it by only 23%. However, in the summer, 48% and 23% more productivity were obtained by adding the second and third collector, respectively. (C) 2015 Elsevier Ltd. All rights reserved.