Peak XV joins UK fintech startup Primer's $100m round

On 20 May 2026, Primer, a UK payments infrastructure startup, said it raised US$100 million in a series C led by Sofina, with Peak XV Partners and existing investors Balderton, Accel, ICONIQ, Tencent, and Speedinvest also joining.

The company said it will use the funds to add more AI tools for payments and finance teams.

It also plans to expand in the US, hire up to 50 people there, and lift the market’s share of revenue from about a fifth to more than a third by 2028.

Founded in 2020, Primer said it helps merchants manage payments across providers and counts GetYourGuide, Dialpad, and Printful as customers.

The new round brings its total funding to US$170 million.

🔗 Source: Primer

🧠 Food for thought

Implications, context, and why it matters.

Primer’s AI push builds on earlier product growth

Primer was last valued at US$425 million after a US$50 million series B round in October 2021 1.
Started by former PayPal staff, Primer set out to bring together payment data from different providers. That work now supports its AI plans 2.
Alongside customers such as GetYourGuide, Primer is also targeting smaller businesses through “Primer for Growth.” The program gives eligible startups one year of free access to Monitors and Observability, tools that track payment performance and catch problems 3.
In research cited by Primer, 94% of startups said their current payment setup would not meet their needs within 12 months 3.

The funding backs more automated work in payments

Primer sells payments infrastructure that helps merchants handle integrations across providers such as Checkout.com, Stripe, and Worldpay, a payments company 1.
It is expanding its AI agent, Primer Companion, so it can run experiments, improve results, and act within limits set by merchants 2.
The move fits a broader shift in business-to-business (B2B) software. AI tools are starting to take action in day-to-day operations, rather than only offer analysis 2.
If that works, it could strengthen the case for autonomous AI in financial operations, where the risk of mistakes has long slowed automation 2.