UK Dividend Tax Explained — Allowances, Rates, and How It Interacts with CGT

Most investors have both capital gains and dividend income. They’re taxed under completely different rules, but they interact in ways that can push you into a higher bracket. Here’s how the dividend side works.

The dividend allowance

For 2025/26, the first £500 of dividend income is tax-free. This is your Dividend Allowance — separate from your Personal Allowance and your CGT Annual Exempt Amount. Above £500, you pay tax at rates that depend on your income tax band:

These rates are set out in HMRC’s dividend tax guidance. They’re lower than the equivalent income tax rates on salary, which is one reason companies sometimes distribute profits as dividends rather than pay.

Like the CGT allowance, the dividend allowance has been slashed in recent years — it was £2,000 as recently as 2022/23, then £1,000, now £500. More people are being caught.

ISA dividends don’t count

Dividends received inside an ISA or SIPP are completely tax-free and don’t count towards your £500 allowance. If your portfolio generates significant dividend income, sheltering it inside an ISA is one of the simplest ways to reduce your tax bill. See our bed and ISA guide for how to move existing holdings.

How dividends affect your CGT rate

This is the interaction most people miss. Dividends are income tax, not CGT. But your total taxable income — including taxable dividends — determines which CGT rate band your capital gains fall into.

If your salary is £35,000 and you receive £5,000 in taxable dividends, your total income is £40,000. After the personal allowance (£12,570), your taxable income is £27,430. But add the dividends and you’re at £32,430 — leaving less room in the basic rate band (£37,700) for your capital gains.

That extra dividend income can push your capital gains from the 18% rate to 24%. On a £10,000 gain, that’s an extra £600 in tax. Our rates guide shows the full band calculation.

US dividends and the W-8BEN form

If you hold US stocks on Robinhood UK, Trading 212, or Tastytrade, the US government withholds 30% of dividends at source by default. That’s a painful hit.

Fill in a W-8BEN form through your broker to reduce the withholding to 15% under the UK-US double taxation treaty. Most brokers prompt you to do this when you open the account, but check if yours is current — they expire every three years.

The 15% you do pay can be claimed as a foreign tax credit on your UK self-assessment, reducing the UK tax on those dividends. Without the W-8BEN, you’re overpaying by 15 percentage points on every US dividend.

Reporting dividends

Dividends go in a different section of your self-assessment than capital gains. Capital gains go on SA108. Dividends go in the main tax return (SA100) or the additional information pages.

You don’t need to report dividends if your total dividend income is under £500. Above that, you declare on your self-assessment. HMRC’s check if you need a tax return tool can help you figure out whether you need to file.

Accumulating funds — a hidden dividend issue

If you hold accumulating ETFs (ones that reinvest dividends internally rather than paying them out), you still owe tax on the income. For offshore funds, this comes through as Excess Reportable Income (ERI). For UK funds, it’s called “notional distribution” — as described in HMRC Helpsheet HS284.

Either way, the income is taxable as dividend income even though you never received cash. The amounts are usually small for modest portfolios, but worth knowing about if your accumulating fund holdings are significant.

TaxBull handles the capital gains side — calculating your CGT with proper HMRC matching rules. For dividend reporting, you’ll need to include it separately in your self-assessment.

This is general information, not personal advice. Consult a tax professional for guidance specific to your circumstances.