Not always. Whether Probate is needed usually comes down to how the deceased's assets were owned and held.
Assets that were jointly owned — a joint bank account or a home held as joint tenants, for example — often pass automatically to the surviving owner without needing Probate.
Property or accounts held solely in the deceased's name, however, will usually require a Grant of Probate before they can be dealt with, which is why it's worth checking rather than assuming either way.
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