Purpose – The efficient management of working capital is of great importance for companies since it is a major aspect of corporate finance and affects their profits. This study has been carried out in order to determine the efficiency with which the companies listed on the Borsa İstanbul (BİST), the Istanbul stock exchange, manage their working capital. Design/methodology/approach - The working capital efficiency of the 127 manufacturing companies shares in which were traded continuously on the stock exchange from 2009 to 2018 were calculated by the index method using data from their quarterly financial statement, descriptive analyzes were carried out on the basis of company and sector. Findings – The analysis determined that the ability of the Istanbul stock exchange manufacturing sector to use its revolving assets to generate sales was at its lowest in the first quarter of 2017 and that its ability to use its revolving assets to generate sales was highest in the fourth quarter of 2017. The individual performances of the components of working capital in the Istanbul stock exchange manufacturing sector were found to have been highest in the first quarter of 2013 and lowest in the second quarter of 2017. Analysis of the levels of efficiency achieved by the manufacturing companies in comparison to the sector as a whole revealed that 45% outperformed the sector, 4% performed in parallel with the sector and 51% underperformed the sector. Discussion – The findings of the study show that the manufacturing companies listed on the exchange generally succeeded in managing their working capital efficiently during the period under examination.