Purpose -The purpose of this paper is to investigate the importance of business lending as a source of bank profits in the UK banking system. The paper also examines whether the profitability of business lending is mostly driven by heterogeneous characteristics of individual banks or whether it is affected by systematic characteristics such as bank size and ownership structure. Findings: Our empirical results show that business lending is a statistically significant determinant of bank profits. However, this average effect masks important systematic differences among banks. In particular, we find strong size effects: the profitability of business lending is considerable for small banks but negligible for large banks. In contrast, we could not detect any ownership effects for domestic and foreign banks. These findings persist when the occurrence of the financial crisis is accounted for.Research limitations/implications: Interestingly, our study relates these findings to the process of financialisation. Yet, the extent of the latter and its impact on various groups of banks (i.e., large, small, domestic and foreign banks) have not been examined. Further research in this area would make an important contribution to the literature.Practical Implications: Our findings suggest that business lending is not a driving factor of profitability for large banks. One possible policy implication -which may be of interest especially to regulators and policy makers -is that capital injections into the larger banks per se are unlikely to lead to an expansion of credit to business. Originality/Value: There is very little research in the literature on the questions addressed in this paper, especially for the UK banking system. Moreover, the process of financialisation, which motivates the enquiry of this paper, is a growing area of research. Thus, the contribution of this paper is twofold.