We need a donation cap, but how much should it be?

In the UK today, there is still no legal limit on how much a single donor can give to a political party each year. That simple fact shapes our politics in profound ways. When unlimited money flows into campaigns from a small group of exceptionally wealthy individuals, it becomes harder for the rest of us to get our voices heard.

Introducing a clear cap on political donations is one of the most effective steps we could take to rebuild trust. With the upcoming Elections Bill, the government has an opportunity to put a donations cap into law.

The question is not whether to cap donations, but where the cap should be set. To understand what is at stake, it helps to look at three possible levels: a high cap of £1,000,000, a mid-level cap of £100,000 and a lower cap of £10,000.

Politics should never be a personal project for the ultra-rich

Setting a donation cap as high as £1,000,000 per year may seem ludicrously generous. In some ways, that is the point. It would still allow political parties to receive sizeable contributions, but it would put a clear boundary around the influence of the very wealthiest citizens.

In recent years, donations of over a million pounds have become common place. Just today, Reform UK were given £9,000,000 by Christopher Harborne, their largest single donation ever, and the largest donation ever from a living donor. The largest single donation ever was £10,000,000 for the Conservatives from Lord John Sainsbury’s will in 2023. The largest donation for the Liberal Democrats was £8,000,000 from Lord David Sainsbury in 2019, while Labour’s was £4,000,000 from Quadrature Capital Ltd in 2024.

With no ceiling at all on how much a wealthy person could give, even larger donations are permissible. Under a cap like this, no individual could single-handedly bankroll a party. That matters. It stops political parties becoming personal vehicles for those who can afford to pour vast sums into the system, and treat political parties like just another yacht or island.

We can reduce elite influence

A cap at £100,000 changes the dynamic more significantly. Contributions at this level can still be generous, but they are no longer so large that a party can revolve around a handful of donors on first name terms with the party leaders.

Under a £100,000 cap, parties would need a broader donor base. This is a model that begins to rebalance power. It reduces the risk that policy priorities are driven by the financial interests of a small elite, and instead are focused on the health of the broader economy. It is a step towards a healthier political culture.

Towards a fairer democracy

The Committee on Standards in Public Life has previously recommended a £10,000 cap on donations from any individual or organisation in any year. Let’s be blunt, the vast majority of people would not be able to donate this kind of money. But a cap of £10,000 would end the era in which political parties can rely on rich benefactors.

That means engaging with more people, building membership and relying less on the biggest cheques. When parties depend on a wider pool of supporters, their incentives change. They must spend more time listening and responding to the concerns of ordinary voters, not just those who can afford to give more.

As Parliament considers reforms to electoral law, this is the moment to commit to a donation cap – meaningful reform starts with limiting how much any one donor can give.