Bridging the Gap: How Banks’ Maturity Mismatch Shapes Monetary Policy Transmission
Working Paper, 2026
Show Abstract
This study examines how maturity mismatches in banks’ balance sheets shape the transmission of
monetary policy to credit supply. Linking supervisory data on approximately 1,800 euro area banks
to loan-level credit records, we show that the role of maturity mismatches is highly
shock-specific. Mismatches amplify the effects of unconventional but not
conventional monetary policies. Banks with larger maturity gaps reduce lending more
sharply following monetary policy surprises regarding quantitative tightening (QT) because
valuation losses on long-term assets negatively affect their net worth, causing tighter leverage
constraints. To rationalize these findings, we develop a medium-scale New Keynesian DSGE model
featuring a segmented financial sector, where intermediaries are differentiated by their maturity
gaps. This framework explains the observed asymmetry: the high-mismatch banking segment is more
exposed to long-duration losses that compress net worth, tighten endogenous leverage constraints,
and amplify real economic effects through an investment wedge, whereas standard policy rate
shocks — which mainly affect short-term rates — generate little heterogeneity in lending
responses.