Are the drivers of domestic and cross-border M&As in the banking sector different? Despite the intense research on bank M&As in the last decade, the attention paid to this issue is surprisingly limited. We fill this gap studying the ex-ante determinants of national and international acquisitions in the banking sector in an unbalanced panel of nearly 1,000 banks from 50 world countries, from 1992 to 2007. Our results show that size and profitability have a stronger impact on the probability that a bank is a bidder in a cross-border deal than in a domestic deal. Consistent with the findings of the literature on the determinants of the internationalization of manufacturing firms, international expansion in the banking sector is therefore easier for countries with a number of large â€œnational championsâ€, that are more capable to overcome the fixed costs of internationalization and have a stronger incentive to diversify the idiosyncratic risks of their domestic activities.