XBT

XBT is a ticker symbol for Bitcoin built on the naming logic of the ISO 4217 currency-code standard, the same system that gives national money three-letter codes like USD or EUR. Assets with no single issuing country, such as gold (XAU) and silver (XAG), get an "X" prefix instead. Because Bitcoin has no central issuer, the community proposed XBT rather than the more intuitive BTC, since "BT" is already reserved for Bhutan and the next obvious option, XBC, belongs to a European unit of account.

The code first circulated informally in 2013 and gained a formal push in 2014, when the Bitcoin Foundation's Financial Standards Working Group applied to have it added to the official ISO 4217 list, building on an earlier public petition. Despite that effort, XBT was never actually ratified by the ISO 4217 Maintenance Agency, so it remains a widely used but unofficial convention rather than a certified standard.

XBT shows up mainly where crypto meets traditional finance. Bloomberg terminals have listed it since 2013, and when CME Group and CBOE launched regulated Bitcoin futures in 2017, both used the XBT symbol to fit systems designed around ISO-style codes. Kraken still applies XBT to its futures contracts, OTC desks, and API, even though it switched spot-market listings to BTC in 2021. Bitcoin itself is unaffected by which label is used: XBT and BTC always refer to the same coin at the same price, so the choice is purely about which naming convention a given platform follows.