This is the peer reviewed version of the following article:Marshall, A., Mccann, L. and Mccolgan, P. (2016), The Choice of Debt Source by UK Firms. Journal of Business Finance & Accounting, 43: 729–764., which has been published in final form at doi: 10.1111/jbfa.12194. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.