This study examines the importance of credit demand and credit supply-relatedfactors in explaining the evolution of credit granted to Portuguese small andmedium-sized enterprises (SMEs). The results suggest that the interest rate is astrong driver of SMEs' demand for bank loans, as well as their internal nancingcapacity. On the other hand, credit supply mostly depends on the rms' abilityto generate cash-ows and reimburse their debt, and on the amount of assetsavailable to be used as collateral. The model was estimated for the period between2010 and 2012, and the estimated coecients were used to compute theprobability of credit rationing. The results suggest that a considerable fractionof Portuguese SMEs were aected by credit rationing in this period.