This study exploits the adequacy of the Monti‐Klein model to analyse the banking firms' lending behaviour and uses the geometric lag analytic model to detect the lifespan of bank conglomeration impacts on small business financial welfare. We find that, although the impact of emerging conglomerate banks on lending to small businesses is significantly negative (δ = −0.6897; p < 0.01), the effect reverses to a pre‐conglomerate positive status within one year. Hence, bank conglomeration does not negatively affect the financial welfare of small business borrowers in the long run. Contrary to the widespread belief and fear, the negative effects are not permanent. Large banks are feared to have no time for mid‐sized businesses. We find, however, that mere increases in size, as may be caused by economic or internal growth, do not pose a threat to small businesses. Large‐sized banking firms positively and significantly correlate with small and predictable risks (δ = 1.7935; p < 0.01). Hence, contrary to what regulators fear, there is no real issue surrounding the idea that building diversifying banks will influence small business loans negatively. What matters is the means through which large banks emerge. Therefore, regulators ought to exercise caution so that they do not discourage their emergence.