This paper provides empirical evidence on the effects of a central bank collateral framework on pricing of pledgeable assets. We investigate a policy modification by the Central Bank of Russia that established a set of local administrations whose debts were accepted as collateral in refinancing operations regardless of their credit ratings. Employing a difference-in-difference approach, we demonstrate that, due to the collateralizability, these administrations obtained a discount of 50 basis points on the interest rates on their credit contracts. Furthermore, we analyze the interest rate offered by multiple banks for the same credit contract as they compete in a formal auction. We document that banks with limited marketable collateral or substantial dependence on central bank funding submitted the lowest bids for contracts eligible as collateral. These findings indicate that asset collateralizability in monetary policy operations can significantly affect bank credit supply.