What you pass on
Rees Calder · 23 April 2026 · 6 min read
In the UK, charitable legacies (bequests in wills) account for roughly £4 billion per year, about 28% of all charitable income from individuals (Remember A Charity consortium data, 2024). In the US, the figure is larger in absolute terms: $45.6 billion in 2023 per Giving USA, roughly 9% of total charitable giving.
These numbers are big, and they come from a relatively small share of estates. Only about 6.3% of UK wills include a charitable bequest (Smee & Ford legacy data, 2024). In the US, roughly 5-8% of estates include charitable bequests (AARP/AEI estimates, 2023).
The implication is clear. Legacy giving is massively underleveraged. A modest increase in the share of wills that include charity would generate billions in additional funding, funded entirely by money the giver will never spend.
Why legacy giving is different
Three features make bequests unlike any other form of giving.
You'll never miss it. Every pound you donate during your lifetime is a pound you could have spent. Every pound you leave in your will is a pound you, by definition, will not spend. The opportunity cost is different. It's not zero (your heirs receive less), but it's the lowest-pain form of giving that exists.
It compounds across generations. James Andreoni's "warm glow" research (1990, Journal of Political Economy) showed that donors give partly for altruistic reasons and partly for the psychological benefit of the act itself. Legacy giving is the rare case where the altruistic motive dominates, because you won't be around to enjoy the warm glow. That self-selection means legacy donors tend to direct funds to high-impact causes rather than feel-good ones.
The tax treatment is exceptionally favourable. In the UK, if you leave 10% or more of your "net estate" (after deducting the nil-rate band, residence nil-rate band, and other reliefs) to charity, the Inheritance Tax rate on the remainder drops from 40% to 36%. This means the effective cost of a charitable legacy is dramatically reduced. HMRC data (2023-24) shows that approximately 3,400 estates per year claim the reduced rate, but eligibility is far wider.
In the US, charitable bequests are fully deductible from the taxable estate with no cap. For estates above the federal exemption ($13.61 million in 2024, though this is scheduled to halve in 2026), the estate tax rate is 40%. A $1 million bequest to charity saves $400,000 in estate tax, meaning the net cost to heirs is $600,000, not $1 million.
The maths that most people don't run
A typical UK estate, for someone who owns a home and has pension savings, is worth roughly £300,000-500,000 (ONS Wealth and Assets Survey, 2024). Take the midpoint: £400,000.
Leaving 1% to charity: £4,000 bequest. At the 40% IHT rate (assuming the estate exceeds the nil-rate band), the cost to heirs is £2,400 (because £1,600 would have gone to HMRC anyway). If the estate qualifies for the 36% reduced rate by leaving 10% or more, the calculation shifts further.
Leaving 10% to charity: £40,000 bequest. The estate now qualifies for the 36% IHT rate. The remaining £360,000 is taxed at 36% instead of 40%, saving £14,400 in IHT. Net cost to heirs of a £40,000 bequest: roughly £25,600. The charity receives £40,000; your heirs lose £25,600. The government absorbs the difference.
This is the single most tax-efficient form of giving available to most UK households. It's not widely known because estate planning is boring and death is uncomfortable to think about.
The behavioural barriers
If the maths is this clear, why do only 6% of UK wills include a charity?
Nobody asks. Solicitors who draft wills rarely prompt clients about charitable bequests. The Remember A Charity campaign has worked for over a decade to change this, and their data shows that when solicitors include a standard prompt ("Would you like to leave a gift to any charity?"), inclusion rates roughly double. The barrier is not unwillingness. It's not being asked.
Wills feel permanent. People fear that including a charity locks them in. It doesn't. You can change your will at any time while you have mental capacity. A charitable bequest is exactly as flexible as any other clause in a will. But the perception of permanence acts as a brake.
The beneficiaries are abstract. You know your children's names. You don't know the name of the person who will benefit from your charitable legacy in 2057. Abstractness reduces motivation. The best way to counter it is to name a specific charity, for a specific reason, in the will itself. "10% of my residual estate to Against Malaria Foundation, because malaria nets work and the evidence is strong" is more psychologically durable than "10% to charity."
What to actually do
Three moves, in order of effort.
Check whether you have a will. Roughly 54% of UK adults don't have one (YouGov/Remember A Charity, 2024). If you don't, make one. The charitable bequest is a bonus; the real reason to make a will is that dying without one creates legal chaos for your family.
Add a charitable clause. If you already have a will, adding a codicil with a charitable bequest typically costs £50-100 through a solicitor, or nothing through free will-writing services offered by many UK charities (including the National Trust, Cancer Research UK, and Macmillan). Specify a percentage of residual estate rather than a fixed sum, so the bequest scales with your assets automatically.
Tell your family. The biggest source of contested charitable bequests is surprise. If your family knows the bequest exists and understands why, the likelihood of challenge drops to near zero. The conversation is awkward. Having it is cheaper than not having it.
The philosophical note
There's a reasonable argument that you should give during your lifetime rather than wait. Peter Singer makes this case: the money does more good now than later, because people are suffering now. If you have the resources to give meaningfully during your lifetime, you should.
The counter-argument: most people don't give meaningfully during their lifetime. The median UK household gives 0.5% of income. If a legacy bequest adds 5-10% of a lifetime's accumulated wealth on top of that, the absolute amount is likely larger than a lifetime of monthly donations. The best shouldn't be the enemy of the good.
Legacy giving and lifetime giving are complements, not substitutes. Do both if you can. If you'll only do one, the legacy is the one that requires the least willpower.
One sentence
A charitable bequest costs you nothing you'll ever spend, saves your heirs money on tax, and adds your lifetime's accumulation to causes that outlast you. Make a will, add a clause.
Sources used: Remember A Charity consortium legacy giving data (2024), Giving USA Annual Report (2024, bequests section), Smee & Ford legacy monitor data (2024), HMRC Inheritance Tax statistics (2023-24), ONS Wealth and Assets Survey (2024), Andreoni "Impure Altruism and Donations to Public Goods" (Journal of Political Economy, 1990), IRS estate tax data and federal exemption thresholds (2024), AARP charitable bequest research (2023), YouGov/Remember A Charity will-writing survey (2024). Full links in the planning doc.