AIM Shares and Inheritance Tax: How the 2026 Relief Changes Work
If you hold AIM-listed shares as part of your inheritance tax planning, the April 2026 reform has halved the relief available. Here is what has changed, what it means for your portfolio, and whether AIM shares still make sense for IHT purposes.
AIM Shares IHT Changes
How AIM Shares Worked for IHT Planning
AIM (the Alternative Investment Market) is the London Stock Exchange's market for smaller, growing companies. Many AIM-listed shares qualified for 100% business property relief, making them one of the few liquid investments that could sit entirely outside your estate for IHT purposes.
The appeal was straightforward: buy qualifying AIM shares, hold them for at least two years, and they passed to your beneficiaries completely free of inheritance tax. Unlike gifts (which require a seven-year survival period), AIM shares offered IHT relief while you retained full ownership and access to the capital.
This made AIM a popular choice for investors in their 70s and 80s who wanted to reduce IHT but did not want to give away their assets during their lifetime. The trade-off was investment risk — AIM shares are more volatile than FTSE 100 stocks and some investors experienced significant losses.
What Changed on 6 April 2026
From 6 April 2026, the relief available on qualifying AIM shares has dropped from 100% to 50%. This applies regardless of the value of the AIM holding and regardless of how long you have held the shares.
Before April 2026: £200,000 of qualifying AIM shares = £0 IHT
From April 2026: £200,000 of qualifying AIM shares = £40,000 IHT (50% relief on £200,000 = £100,000 taxable at 40%)
Additionally, AIM shares count toward the new £2.5 million combined APR/BPR allowance. If you hold both business assets and AIM shares, the allowance is shared between them. Read our full guide to the APR/BPR reform for details on the £2.5 million cap.
Is It Still Worth Holding AIM for IHT Purposes?
The short answer: possibly, but the case is weaker than it was. Here are the numbers:
Susan holds £300,000 in qualifying AIM shares. She also has other estate assets of £400,000 (house and savings). Her nil-rate band is £325,000 and she qualifies for the £175,000 RNRB.
| Scenario | AIM relief | Taxable value of AIM | Total taxable estate | IHT at 40% |
|---|---|---|---|---|
| Before April 2026 (100% BPR) | £300,000 | £0 | £0 | £0 |
| From April 2026 (50% BPR) | £150,000 | £150,000 | £50,000 | £20,000 |
| No BPR at all (e.g., FTSE 100 shares) | £0 | £300,000 | £200,000 | £80,000 |
Even with halved relief, Susan's AIM shares save her estate £60,000 in IHT compared to holding non-qualifying investments. The saving is real, but it is now £60,000 rather than £80,000.
The Investment Risk Factor
AIM shares carry higher investment risk than mainstream equities. The typical AIM portfolio can experience significant volatility. Before 6 April 2026, the 100% IHT relief offset this risk for many investors. With relief now halved, the risk-reward balance has shifted:
- A 20% drop in your AIM portfolio's value could wipe out the IHT saving entirely
- The reduced relief means you need the AIM shares to at least hold their value to come out ahead
- Alternative strategies (such as gifting or life insurance in trust) may now offer comparable IHT benefits with lower investment risk
The Interaction with the £2.5M APR/BPR Allowance
AIM shares count toward the combined £2.5 million APR/BPR allowance. This matters if you also hold other qualifying business or agricultural assets:
- If your total qualifying assets (business + agricultural + AIM) are under £2.5 million, the allowance is less relevant — but AIM shares still only get 50% relief
- If your qualifying assets exceed £2.5 million, AIM shares above the cap receive 50% relief on 50% of the value — effectively only 25% relief on the excess
- Consider whether the APR/BPR allowance is better allocated to business assets (which still receive 100% relief within the allowance) rather than AIM shares (which receive only 50%)
If you hold both a qualifying business and AIM shares, the £2.5 million allowance is automatically applied to whichever assets give the most relief. In practice, this means 100%-relief business assets are sheltered first, and AIM shares use any remaining allowance at 50%.
David owns a qualifying farm worth £2 million and a qualifying AIM portfolio worth £1 million. His combined APR/BPR assets total £3 million.
| Asset | Value | Relief | Taxable |
|---|---|---|---|
| Farm (within £2.5m allowance) | £2,000,000 | 100% APR | £0 |
| AIM shares (within £2.5m allowance) | £500,000 | 50% BPR | £250,000 |
| AIM shares (above £2.5m allowance) | £500,000 | 50% BPR | £250,000 |
| Total taxable from APR/BPR assets | £500,000 | ||
The first £2.5 million of combined assets uses the allowance — the farm gets 100% relief, but the AIM shares within the cap still only get 50% relief. The remaining £500,000 of AIM shares above the cap also gets 50% relief. The result: £500,000 taxable, or £200,000 IHT at 40% (before other allowances).
If David held only the £1 million AIM portfolio with no farm, the entire AIM holding would fall within the £2.5 million allowance — but still only receive 50% relief, giving £500,000 taxable.
What Should AIM Investors Do Now?
- Do not panic-sell. Selling AIM shares could trigger capital gains tax and you lose the remaining 50% BPR benefit. The decision to sell should be based on investment merit and your overall financial plan, not a knee-jerk reaction to the relief change.
- Review the purpose of your AIM holdings. If you hold AIM purely for IHT, reconsider whether the reduced benefit justifies the investment risk. If you hold AIM for growth potential and IHT was a bonus, the investment case may still hold.
- Model your estate. Use Estate Map's calculator to see how the AIM relief change affects your total IHT position. The impact depends on your other assets, allowances, and reliefs.
- Consider alternatives. For investors whose primary goal is IHT mitigation, life insurance in trust or regular gifting strategies may now offer a more predictable route to reducing IHT.
- Take professional advice. A qualified financial adviser can help you weigh the IHT benefit against investment risk and compare AIM with other planning strategies.
Frequently Asked Questions
What happens to AIM shares and inheritance tax from April 2026?
From 6 April 2026, qualifying AIM shares receive only 50% business property relief, down from 100%. This means AIM shares face an effective inheritance tax rate of 20%, where previously they could pass completely IHT-free after being held for two or more years.
Do AIM shares count toward the £2.5 million APR/BPR allowance?
Yes. AIM shares that qualify for BPR count toward the combined £2.5 million APR/BPR allowance. However, because AIM shares only receive 50% relief (not 100%), the relief available on AIM shares is less generous than on other qualifying business assets within the allowance.
Is it still worth holding AIM shares for IHT planning?
AIM shares still offer a 50% IHT relief — an effective 20% tax rate compared to the full 40% rate on non-qualifying assets. Whether they remain worthwhile depends on your overall estate plan, investment objectives, and risk tolerance. The IHT benefit is now smaller but has not disappeared entirely.
Does the AIM BPR reduction apply to existing holdings?
Yes. The reduction from 100% to 50% BPR applies from 6 April 2026 regardless of when the AIM shares were purchased. There is no grandfathering of existing holdings — all qualifying AIM shares are subject to the new 50% relief rate.
How long do I need to hold AIM shares to qualify for BPR?
AIM shares must be held for at least two years before death to qualify for business property relief. This requirement has not changed under the April 2026 reforms — only the rate of relief (from 100% to 50%) has changed.
Calculate the Impact on Your AIM Portfolio
Enter your AIM share holdings alongside your other estate assets. Estate Map shows you the IHT position under the new 50% relief rules.
Calculate my IHT →This article is for educational purposes only and does not constitute financial advice. AIM share investments carry risk and the value of your holdings can go down as well as up. Always consult a qualified financial adviser before making investment or estate planning decisions.