Recent theory suggests that balance sheet frictions and constraints faced by financial intermediaries can have major asset pricing implications. We propose a new measure of the impact of these constraints on intermediary funding costs that is based on the implied cost of renting intermediary balance sheet space. On average, balance sheet constraints add 81 basis points to intermediary funding costs, but the impact often exceeds 200 basis points during a crisis. We find that these balance sheet costs have real effects on intermediary investment decisions and asset holdings. Increases in balance sheet costs are associated with short-term increases in the use of derivatives, but longer-term declines in risk-taking by financial institutions. Balance sheet costs introduce a wedge between on-and off-balance-sheet investments which may help resolve a number of asset pricing puzzles.There is an extensive literature on how the various types of balance sheet constraints faced by financial intermediaries may affect asset prices. A number of recent papers have focused on the implications of collateral constraints, funding liquidity, margin requirements, leverage constraints, regulatory capital requirements, and other types of balance sheet frictions and restrictions for financial markets.There is also a rapidly growing literature on the potential impact on asset prices and market liquidity of recent legal and regulatory measures including the Dodd Frank Act, the Volcker Rule, and the Supplementary Leverage and the Liquidity Coverage Ratios of Basel III. . This issue has also been extensively discussed among industry participants and policy makers are actively considering the impact of these regulatory measures on market liquidity. Recent examples include the International Capital Market Association (2015) and Chen, Korapaty, and Swaminathan (2016). This paper contributes to this literature in several ways. First, we provide strong evidence that the relative pricing of Treasury securities in the cash and futures markets is directly related to the balance sheet constraints faced by financial intermediaries. Second, we show that increases in balance sheet costs have real effects on the leverage, holdings of Treasury securities, and asset growth rates of financial intermediaries, as well as on the use of derivatives by market participants. Third, our measure of the impact of balance sheet constraints provides a metric for monetary policy authorities and others for evaluating the effects of capital regulation on financial markets. Fourth, our results provide a framework for resolving a number of puzzling asset pricing anomalies involving financial derivatives and cash market instruments. Finally, our results provide direct empirical support for the rapidly growing literature on intermediary asset 4