An ETF’s cost is typically expressed through its expense ratio, representing the percentage of assets under management (AUM) that investors pay annually to cover the fund’s administrative and operational expenses. This ratio, in general, covers various costs and is lower for the majority of ETFs, making them more cost-effective.  However, the specific expense ratio can vary widely based on the ETF type and its investment approach. For example, while the expense ratio of passive ETFs is typically low, actively managed ETFs often have higher expense ratios.