The ISO 4217 code for the British pound is GBP.
ISO 4217 is the international standard that assigns three-letter codes to currencies and funds. GBP identifies pound sterling, the currency of the United Kingdom and several associated territories. It is used by banks, payment systems, businesses, exchange-rate services and international financial markets.
The code combines “GB,” the ISO country-code element for the United Kingdom, with “P,” the first letter of “pound.” The pound sign, £, is a symbol rather than the standardized three-letter code, so GBP is especially useful when currencies need to be identified unambiguously in international transactions.
Several tempting alternatives are wrong. UKP is not the official ISO code, BPD reverses the relevant letters and adds the wrong final letter, and GBR is the country code commonly associated with Great Britain—not the currency code. GBP's ISO numeric code is 826.