United Kingdom Financial Glossary
Learn the definitions of key financial terms, tax acronyms, and mortgage jargon commonly used in United Kingdom. Updated for 2026.
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Stocks & Shares ISA Interest Tax
InvestmentsFrom 6 April 2027, ISA managers owe a charge at the savings basic rate on cash-deposit interest inside stocks and shares or innovative finance ISAs; that rate is 22% for 2027-28.
View full definition →Stablecoin
InvestmentsA cryptoasset designed to track a fiat currency; UK stablecoin-issuer rules were finalised in June 2026 but the expanded authorisation regime starts on 25 October 2027.
View full definition →UK financial terms for the 2027 ISA reform and crypto regulation era
The cash ISA changes take effect on 6 April 2027 under SI 2026/1018. Separately, the FCA's expanded cryptoasset authorisation regime begins on 25 October 2027. These terms explain the specific mechanisms that affect how you save, invest, and interact with digital assets in the UK.
The 2027 ISA restructuring
SI 2026/1018 takes effect on 6 April 2027. A saver aged 64 or under at tax-year end may subscribe £12,000 annually to cash ISAs; at 65 or over the cash limit remains £20,000. The unused £8,000 of overall ISA allowance can go into a non-cash ISA or remain unused. From the same date, interest on cash deposits held within stocks and shares or innovative finance ISAs faces a charge at the savings basic rate, enacted as 22% for 2027-28. The age exemption applies to the cash subscription cap, not this interest charge.
FCA crypto and stablecoin authorisation
The FCA published final rules for new cryptoasset and stablecoin activities in June 2026, but the expanded FSMA authorisation regime starts on 25 October 2027. Firms seeking transitional status can apply from 30 September 2026 to 28 February 2027. Existing AML registration and crypto financial-promotion rules are separate from that future authorisation. A register entry does not make the cryptoasset itself a protected deposit; the FSCS says cryptoassets are not covered.