Plain English definitions
CIS and construction tax glossary
50 definitions of the terms UK construction subcontractors and contractors actually need to understand. Written by specialist CIS accountants. All figures updated for 2026/27.
8 definitions
CIS fundamentals
10 definitions
Deductions and rates
CIS deduction
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Deduction rates (0%, 20%, 30%)
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Labour-only deduction base
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Materials deduction
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Verification number
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Payment and deduction statement
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Allowable Expenses (CIS)
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AMAP Mileage Rates
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Class 4 National Insurance
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CITB Levy
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17 definitions
Returns and compliance
CIS300 Monthly Return
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Nil Return
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Pre-notification of Inactivity
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Regulation 24ZA (Public Sector Exemption)
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Late Filing Penalties (CIS)
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Compliance Test
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Turnover Test
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Business Test
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Due Diligence (April 2026)
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Knew or Should Have Known Standard
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Section 62A Penalty
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Section 62B Penalty
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Five-Year Reapplication Ban
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Verification (Subcontractor)
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Employment Status
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Retention Payments
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EPS (Employer Payment Summary)
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6 definitions
Refunds and repayments
3 definitions
Business structures
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