AbstractThis study investigates debt market effects of research and development (R&D) costs capitalization, using a global sample of public bonds and private syndicated loans issued by public non‐financial firms. Firstly, we show that firms capitalize larger amounts of R&D in a year when they exhibit a propensity for issuing bonds, rather than borrowing funds privately from the syndicated loan market, in the subsequent year. Secondly, we provide evidence that capitalized R&D investments reduce the cost of debt. We infer that debt market participants are able to identify firms’ motives for R&D capitalization, as we find a reduction in the cost of debt only for those firms that do not show indications of employing R&D capitalization for earnings management reasons. Indeed, only for this sub‐sample of firms, the amount of capitalized R&D contributes positively to future earnings. We confirm that R&D capitalization is positively associated with audit fees and thus can be deemed to be a signaling device. Lastly, we find that it is the amount of R&D a firm is expected to capitalize and not the discretionary counterparts, which facilitates a firm's access to public debt markets, reduces bond and syndicated loan prices, and contributes to future benefits.