Your funds are held in segregated client accounts at the Bank of London which, in turn, stores those funds unencumbered at the Bank of England. The Bank of London is also part of the Financial Services Compensation Scheme, protecting eligible deposits as well.
DOS & Co. is your bare trustee. In the unlikely event of its insolvency, your funds are not available to its creditors and the administrators would contact you to arrange the return of your funds from the Bank of London.
If the Bank of London becomes insolvent, your funds will not be available to its creditors. We will work with the administrators to release your funds and return them to you or, if possible, to deal with the Bank of England with a view to stepping into the Bank of London's shoes to maintain your accounts with them.
In theory, before a central bank would become insolvent, it would be able to print more money. International credit rating agencies keep track of banks and bond issuers to give clients and potential clients an idea of their ability to repay funds - you can see the Bank of England's Fitch rating here.
The Bank of London is FSCS registered - you can access more information here. More information on the FSCS (including on eligibility) is available here.