Monetary policy has significantly heterogeneous effects on private consumption, which depend on the household's debt and balance sheet position. This column suggests that households with mortgage debt behave in a liquidity-constrained manner, while those without are far less sensitive to movements in interest rates. Though the direct channel of monetary transmission – i.e. the movement in interest cash flows – also affects the expenditure of mortgagors, most of the aggregate effect comes via the stimulus to the income of all housing tenure groups.