This article considers, briefly, whether a claim for payment in cryptocurrency can (arguably) be brought as a claim in debt. It also considers the implications of such a characterisation in two specific areas of insolvency law – petitions for bankruptcy, and whether a proof of debt based on a cryptocurrency payment obligation can benefit from the Insolvency (England and Wales) Rules 2016 (IR 2016) r 14.21, which values the claim in sterling by reference to the exchange rate at the commencement of insolvency. These issues are likely to interest lenders under crypto-loans (which we shall call “crypto-lenders”), insolvency practitioners, and others in the crypto space.