You can sell stock without paying taxes on the gains if your total taxable income falls within the 0% long-term capital gains bracket, which for 2026 is up to $49,450 for singles and $98,900 for married couples filing jointly; however, you're also tax-free on gains in retirement accounts like IRAs/401(k)s (deferring tax) or Roth IRAs (tax-free withdrawals). Remember, short-term gains (held under a year) are taxed as ordinary income, and the key is your total income, not just the stock sale amount.
Each tax year you receive a CGT tax-free allowance or Annual Exempt Amount (AEA). For the current tax year the allowance is £3,000 for individuals and personal representatives, and £1,500 for most trustees.
The 20% rule for capital gains refers to the highest federal tax rate for long-term capital gains, applying to higher income brackets when you sell investments (stocks, real estate) held for over a year, with lower rates of 0% and 15% for lower incomes, and even higher rates for special assets like collectibles. This rate kicks in for single filers earning over approximately $492,300 (2024) or $533,401 (2025), and higher for joint filers, making holding assets over a year a key tax strategy.
When you come to sell or give away shares, you may have to pay capital gains tax, if they've risen in value since you bought or were given them. However, as with dividend tax, you have an annual capital gains tax allowance. It is only when your gains exceed this allowance that CGT is charged.
Failure to report income from taxable share dividend payments, sale of shares or savings interest is tax evasion and can result in an HMRC fine and payment of the outstanding amount of tax.
To avoid the UK's 60% tax trap (an effective 60% rate on income between £100k-£125k), the key is to reduce your adjusted net income back below £100,000 by making tax-efficient contributions, primarily via pension contributions, which reclaim your full £12,570 Personal Allowance, and also through salary sacrifice for benefits like childcare or cycle-to-work, and Gift Aid donations to charity.
On a $100,000 capital gain, you'll likely pay 15% for long-term gains, resulting in about $15,000 in federal tax (plus potential state tax), but it could be 0% or 20% depending on your total taxable income and filing status, while short-term gains are taxed as ordinary income (potentially 22-24%).
The simplest way to reduce capital gains tax is to invest within an individual savings account (ISA). The ISA allowance is currently £20,000 a year3 and all growth and income within the ISA is free from CGT and income tax.
Strategies to Reduce Capital Gains Tax (CGT)
When you sell appreciated stocks within a retirement plan, you'll face no federal taxes on the sale at that time. However, with a traditional IRA or 401(k), you'll eventually pay ordinary income taxes on gains, earnings and your original contributions when you take withdrawals. So taxes are only deferred.
To avoid the higher ordinary income tax rates on stock profits (short-term), you must hold the stock for more than one year, qualifying for the generally lower long-term capital gains tax rates; selling after one year or less results in short-term gains taxed at your regular income bracket, while holding over a year offers preferential rates, potentially saving you significantly on taxes.
Capital gains tax is based on an investor's marginal tax rate, which means it is determined by the tax bracket they fall into. However, there is a special provision that allows for a 50% discount on capital gains if the investment has been held for more than 12 months.
Even if you don't sell your winning stocks, you can create room to take profits by offsetting them with losses elsewhere in your portfolio. This strategy, called tax-loss harvesting, helps minimize the tax impact of realizing gains, making it easier to access value when you need to.
The "6-year rule" for Capital Gains Tax (CGT) in Australia allows you to treat a former main residence as tax-exempt for up to six years after you move out, even if you rent it out, enabling you to avoid CGT on any growth during that period. You qualify by moving out, choosing to treat it as your main home for tax, and can reset the rule by moving back in. If you rent it out for longer than six years, only the portion of the gain after the six-year mark becomes taxable.
How is Capital Gains Tax calculated? Each tax year you can make a set amount in capital gains before paying any tax – this is known as the 'annual exempt amount', or more simply your 'CGT allowance'. This tax year (2025/2026) it's £3,000. You only pay tax on any gain over your allowance each tax year.
Capital gains tax rates
A capital gains rate of 0% applies if your taxable income is less than or equal to: $48,350 for single and married filing separately; $96,700 for married filing jointly and qualifying surviving spouse; and. $64,750 for head of household.
FAQs on UK Taxation
Why do the rich pay less tax? The rich often pay less tax due to the use of tax-efficient strategies, such as investing in capital gains assets, maximising pension contributions, and utilizing tax-advantaged accounts like ISAs.
If you return to the UK within 5 years
You may have to pay tax on certain income or gains made while you were non-resident. This doesn't include wages or other employment income.