Plain English definitions
UK business tax & finance glossary
25 definitions of the terms UK business owners actually need to understand. Written by ICAEW qualified accountants. All figures verified for 2025/26.
Compliance
Tax
BADR (Business Asset Disposal Relief)
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Section 455 (Director's Loan Tax Charge)
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AIA (Annual Investment Allowance)
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R&D Tax Credits
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Corporation Tax
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Personal Allowance
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Dividend Allowance
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National Insurance Contributions (NI)
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PAYE (Pay As You Earn)
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EIS and SEIS (Investment Tax Reliefs)
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Capital Gains Tax (CGT)
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