We document that M&A withdrawals are more sensitive to acquirers' announcement returns when the deal is financed entirely with cash, suggesting an intriguing interaction between payment methods and market feedback. Motivated by this evidence, we develop a model in which managers learn about deal synergies from post-announcement stock prices, with the payment method shaping the informativeness of this feedback. Our theory not only explains these differing feedback patterns but also yields unique predictions for how the choice of payment method depends on financial market characteristics. We test these predictions in a merger-arbitrageur setting and find supporting evidence.