Golub Capital BDC, Inc. Portfolio Composition as of September 30, 2017

Golub Capital BDC, Inc. (“we” or “us”) seeks to create a diverse portfolio that includes senior secured, one stop, mezzanine and second lien loans and warrants and minority equity securities by investing approximately $5 to $30 million of capital, on average, in the securities of middle-market companies. We may also selectively invest more than $30 million in some of our portfolio companies and generally expect that the size of our individual investments will vary proportionately with the size of our capital base.

As of September 30, 2017, we had debt and equity investments in 185 portfolio companies, excluding our investments in SLF, with a fair value totaling $1,685 million.

Asset Mix – as of September 30, 20171

Industry Composition – as of September 30, 20171

1. We have based the statements included in this presentation on information available to us on the date of this presentation, and we assume no obligation to update any such statements. Future results could differ materially from historical performance. Although we undertake no obligation to revise or update any of these statements, whether as a result of new information, future events or otherwise, you are advised to consult any additional disclosures that we may make directly to you or through reports that we have filed or in the future may file with the Securities and Exchange Commission (“SEC”), including annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K.

This presentation contains statistics and other data that have been obtained from or compiled from information made available by third-party service providers. We have not independently verified such statistics or data.