Tax Glossary — US, UK & UAE Terms Explained Plainly

United States

Form 1040: The US individual income tax return. Citizens and green-card holders file it on worldwide income, wherever they live.
FBAR (FinCEN 114): A report of foreign bank accounts, required when your non-US accounts together exceed $10,000 at any point in the year. Informational, but non-filing penalties are severe.
FATCA (Form 8938): A separate disclosure of foreign financial assets above certain thresholds, filed with your tax return — distinct from, and in addition to, the FBAR.
Streamlined Filing: An IRS amnesty letting Americans who non-willfully missed foreign-income or FBAR filings catch up — typically penalty-free for those living abroad.
S-Corporation: A US tax election letting a company's profit pass through to owners, splitting it into salary (taxed) and distributions (no self-employment tax) — often saving tax above ~$60–80k of profit.
Sales-Tax Nexus: The connection that obliges you to collect a US state's sales tax. Since Wayfair, crossing ~$100,000 of sales into a state creates it without any physical presence.
NIIT: The 3.8% Net Investment Income Tax on investment income (including capital gains) once income exceeds $200,000 single / $250,000 married filing jointly.
W-2 vs 1099: A W-2 means you're an employee (tax withheld, employer pays half your payroll tax). A 1099 means you're a contractor — nothing withheld, both halves of payroll tax are yours.

Self Assessment: The UK system for reporting income not taxed at source — the SA100 return, due online by 31 January after the tax year.
PAYE: "Pay As You Earn" — the system by which UK employers deduct income tax and National Insurance from wages and pay them to HMRC in real time (RTI).
CT600: The UK corporation tax return a limited company files with HMRC, due 12 months after year end (with the tax itself due 9 months and a day after).
IR35: Rules taxing you like an employee if your contract-through-a-company arrangement resembles disguised employment. For medium/large clients, the client decides your status.
Making Tax Digital (MTD): HMRC's move to digital records and software-filed returns. Live for VAT, and from April 2026 for income tax for the self-employed and landlords over £50,000.
VAT Registration Threshold: £90,000 of taxable turnover in any rolling 12 months — cross it and VAT registration is mandatory. Voluntary registration is allowed below it.
Dividend Allowance: The slice of dividends taxed at 0% — just £500 for 2026/27. Above it, dividends are taxed at 10.75% / 35.75% / 39.35% depending on your band.
National Insurance: A UK tax on earnings funding state benefits and pensions, paid by employees, employers and the self-employed at different rates.
CGT Annual Exempt Amount: The tax-free slice of capital gains each year — £3,000 for 2026/27. Gains above it are taxed at 18% or 24%.

UAE Corporate Tax: A 9% tax on business profits above AED 375,000, in force for financial years from June 2023. The first AED 375,000 is taxed at 0%.
Qualifying Free Zone Person (QFZP): A free-zone company that can keep a 0% Corporate Tax rate on qualifying income — provided it meets substance, de-minimis and documentation tests.
UAE VAT: A 5% value-added tax in force since 2018. Registration is mandatory above AED 375,000 of taxable supplies, voluntary from AED 187,500.
WPS: The UAE Wage Protection System — salaries must flow through approved channels in a prescribed format, proving employees are paid on time.
End-of-Service Gratuity: A statutory UAE payment on leaving employment — 21 days' basic pay per year for the first five years, 30 days thereafter, capped at two years' pay.
Small Business Relief: A UAE election treating a business with revenue at or below AED 3 million as having no taxable income, available for tax periods up to the end of 2026.
Economic Substance (ESR): Rules requiring UAE entities in certain activities to demonstrate real substance — staff, premises and decision-making — in the Emirates.

Tax Residency: The status that determines which country can tax your worldwide income — decided by day-counting tests, ties and treaties, not just where you hold a passport.
Double Tax Treaty: An agreement between two countries that stops the same income being taxed twice, by allocating taxing rights and granting credits or exemptions.
Transfer Pricing: The rule that transactions between related companies (and connected persons) must be priced at arm's length, as if between independent parties.
Permanent Establishment (PE): A taxable business presence in a country — an office, a dependent agent, sometimes just key people — that can trigger a tax-filing obligation there.
Withholding Tax: Tax deducted at source on cross-border payments such as dividends, interest or royalties, often reducible under a double tax treaty.
CRS: The Common Reporting Standard — the global automatic exchange of financial-account information between tax authorities, including the UAE and UK.

Definitions are the easy part. Knowing how they apply to your situation, across three countries, is the engagement. Ask us.