Deposit insurance is described as a limit on an amount, but the limit attaches to a combination of depositor, institution and account category. The details decide the outcome.
The unit of protection is not the account
Coverage is calculated per depositor at each insured institution, not per account. Several accounts held individually at one bank are added together and share a single limit.
Opening additional accounts at the same bank therefore does not increase protection. Spreading balances across separate insured institutions does.
This distinction accounts for most of the confusion, since account numbers are visible and ownership categories are not.
Ownership categories are counted separately
Funds held individually, jointly, or in certain trust and retirement arrangements are typically treated as distinct categories, each with its own limit at the same institution.
A joint account is generally attributed to its owners in equal shares, so each owner's portion counts towards their own separate joint-account allowance.
The precise categories and how they combine vary by country and change over time, so the rules of the relevant scheme are what govern any particular situation.
Brands and charters are not the same thing
Insurance attaches to the licensed institution. Several consumer brands can sit on a single charter, in which case balances across those brands share one limit.
Conversely, a group can hold multiple separate licences, and deposits at each are protected independently even though the parent company is the same.
Checking the licence behind a brand matters most for savers spreading money specifically to stay within limits at several institutions.
What falls outside the scheme
Investment products sold through a bank are generally not covered, including funds, securities, annuities and most insurance contracts, even when purchased in a branch.
Deposits held at institutions that are not members of the scheme, including some payment platforms that hold balances through partner banks, may be protected differently or not at all.
The distinction between a deposit and a stored balance at a non-bank has become harder to see as apps present both in identical terms.
What happens when a bank fails
The usual resolution is a transfer of insured deposits to a healthy institution, often over a weekend, so access continues with minimal interruption.
Where no buyer is found, the scheme pays insured amounts directly, typically within a short statutory window. Uninsured balances become claims in the resolution process.
Those claims may eventually recover part of their value, but the timing is uncertain and the money is unavailable meanwhile, which is the practical cost of exceeding a limit.