Smes are expected to significantly play a substantial role in stimulating economic development for both developed and developing nations. While their access to bank financing has been widely studied in the empirical literature, the relationship between the levels of bank borrowing and financial performance has received negligible empirical attention. To address this gap, this article examines the relationship between bank borrowing levels as a source of working capital finance needs and the financial performance of SMEs in Cameroon. Specifically, (1) the effect of levels of bank borrowing on the profitability (GPM & ROE) of SMEs, and (2) the effect of levels of bank borrowing on the financial efficiency (OER & ATR) of SMEs in Cameroon. The study made use of the Cameroon World Bank Enterprise survey of 2016. The study’s findings indicate that while increased bank borrowing positively impacts profitability, this effect intensifies from level 1 to level 2, then diminishes from level 3 to level 4. Regarding financial efficiency, SMEs bank borrowing exhibits both positive and negative effects. Specifically, borrowing at levels 1 and 2 enhances financial efficiency, whereas levels 3 and 4 diminish it. These results suggest that SMEs should restrict their bank borrowing to level 2 of their working capital finance needs for optimal financial performance.