It depends on the banking licence they operate under. Some brands can be split across different licences depending on the product.
Lloyds Bank plc includes: Lloyds Bank, Lloyds Bank Private Banking, C&G Savings, Worldwide Service (and others)
https://www.lloydsbank.com/legal/financial-services-compensation-scheme.asp
https://www.fscs.org.uk/what-we-cover/products/banks-building-societies/lloyds/
Halifax operates under the banking authorisation of
Bank of Scotland plc, includes: Halifax, Intelligent Finance (IF), Birmingham Midshires (BM Savings), Bank of Scotland, Bank of Scotland Private Banking, Bank of Scotland Germany, Lloyds Bank (in The Netherlands only), Bank of Wales and St. James's Place Bank.
https://www.fscs.org.uk/what-we-cover/products/banks-building-societies/halifax/
https://www.bankofscotland.co.uk/fscs/
Iweb's FSCS limit applies across: IWeb Share Dealing, Halifax Share Dealing, Lloyds Bank Direct Investments, Bank of Scotland Share Dealing.
http://www.iweb-sharedealing.co.uk/about-iweb/financial-services-compensation-scheme.asp
Each bank should have an FSCS Information Sheet which details which licence and which brands and products are used.
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