SEDOL

A SEDOL (Stock Exchange Daily Official List number) is a seven-character identifier assigned by the London Stock Exchange to securities traded or settled in the UK and Ireland, including fund share classes. The first six characters are alphanumeric and the seventh is a check digit calculated from a weighted sum. Older SEDOLs are purely numeric; newer ones begin with a letter, and vowels are never used to avoid spelling words.

The SEDOL is the national identifier inside a GB or IE ISIN: the ISIN is the country prefix, two zeros, the SEDOL and a final ISIN check digit. IE00B4L5Y983 therefore contains the SEDOL B4L5Y98.

Why it matters

UK platforms, custodians and back-office systems often key on SEDOL rather than ISIN, and Irish-domiciled UCITS ETFs, which make up a large share of the European ETF market, carry SEDOLs because their ISINs are issued in Ireland. If your users or data feeds arrive with SEDOLs, you need to convert them before calling an ISIN-based API.

In the API

FundFacts API is keyed on ISIN, so a SEDOL must be converted first. For GB and IE securities the conversion is mechanical: prepend the country code and 00, then compute the ISIN check digit.

json
{
  "isin": "IE00B4L5Y983",
  "name": "iShares Core MSCI World UCITS ETF USD (Acc)",
  "cached": true
}

Response header fields shown; the payload itself does not repeat the SEDOL.

Common pitfalls

• A SEDOL identifies a security, not a listing, so it does not tell you which exchange to trade on. That is the ticker's job.
• Never store SEDOLs as numbers: leading zeros and letters are significant.