Borrowers with a pair of mortgages collateralized by the same property sometimes continue to make payments on one while defaulting on the other. We articulate a framework for understanding this performance mismatch that emphasizes two types of borrowers: those with stable equity positions who perceive they are facing moderate or temporary liquidity shocks, and those facing severe financial stress in combination with negative equity. The former have an incentive to enter mismatch and subsequently cure, while the latter would default on both contracts. Our empirical analysis using newly available, national samples of matched first‐ and second‐lien mortgages supports this view.