Firms choose between bank lines of credit and commercial paper by weighing cost, flexibility, and the risk that short-term funding will suddenly disappear. Academic and central bank research shows these are complementary tools: banks supply committed liquidity while commercial paper gives access to often cheaper, market-based short-term funding when investor appetite is strong.
Cost, scale, and informational requirements
Commercial paper typically offers lower nominal interest for large, highly rated issuers because the market prices credit and liquidity risk transparently. Gary Gorton Yale School of Management has documented how market funding can be cheap in normal times but vulnerable to sudden withdrawals. By contrast, Douglas Diamond University of Chicago Booth School of Business and others emphasize the informational and monitoring role of bank relationships: banks accept lower transparency, provide commitment value, and underwrite idiosyncratic risks that markets may not price efficiently. For many mid-sized and smaller firms, Allen Berger University of South Carolina and Gregory Udell Indiana University Kelley find that relationship lending remains essential because commercial paper markets demand public ratings and scale.Liquidity risk, regulation, and consequences
Empirical work on the 2007–2009 crisis shows the systemic consequences of reliance on market funding. Andrew Covitz Federal Reserve Bank of New York, Nellie Liang Brookings Institution, and Gustavo Suarez Federal Reserve Bank of New York trace how asset-backed commercial paper froze, prompting the Federal Reserve to create the Commercial Paper Funding Facility to restore intermediation. That episode illustrates the rollover risk trade-off: commercial paper can lower financing cost but creates exposure to investor sentiment and runs. Regulation also matters: Bank for International Settlements reports that post-crisis liquidity and capital rules change banks’ capacity to supply committed lines, affecting firms’ funding mixes across jurisdictions.Firms therefore decide based on predictable determinants: credit rating and access to capital markets, size and predictability of short-term needs, the value of banking relationships for informational opacity, and the regulatory environment in their territory. Cultural and territorial nuances matter—in many emerging markets, shallower commercial paper markets and stronger relationship norms tilt firms toward bank lines, while large multinationals in deep financial centers can substitute market paper when investor confidence is high. The practical consequence is a blended strategy: maintain committed bank lines as insurance and use commercial paper opportunistically to minimize funding cost while actively managing rollover and liquidity risk.