Isometric has partnered with global insurance intermediary group Howden to launch an open Request for Proposals (RFP) through which insurers can apply for approval to offer corresponding adjustment (CA) insurance to carbon removal suppliers registered with Isometric.
The RFP follows Isometric's approval by the International Civil Aviation Organization (ICAO) in November 2025 to issue certificates under the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), the UN-backed global framework that requires airlines to offset emissions from international flights above 2019 levels.
What is CA insurance, and why does it matter?
When a carbon certificate is issued under CORSIA, the host country must authorize a corresponding adjustment, a formal accounting entry that ensures the certificate isn't counted twice toward climate targets. CA insurance protects against the risk that a host country reverses authorization after issuance, which would render the certificate ineligible for CORSIA compliance.
Developers holding an approved CA insurance policy can use it in place of a contribution to Isometric's buffer pool. Approved insurers will be listed on the Isometric Registry, giving developers a clear and straightforward route to compliance.
Applications to the RFP will be assessed against Isometric's CORSIA Supplier Insurance Policy, which sets out the criteria an insurance policy must meet to be approved.
Meeting demand
The RFP widens access to CA insurance, helping CORSIA-eligible supply scale to meet rising airline demand. IATA estimates airlines will require around 500 million tonnes of carbon removal annually by 2050 to reach net zero.
Charlie Pool, Head of Carbon Advisory, Howden, said: "The demand for durable carbon removal is expected to increase significantly over the coming decades. Meeting that demand will require not only high-quality projects, but also the financial and risk-management infrastructure that allows those projects to grow. We're delighted to be partnering with Isometric to help build that foundation."
Isometric has also published a standardized Letter of Authorization template, giving project developers and host country governments a ready-made, ICAO-aligned document to work from.
Insurers interested in applying can submit to the RFP here.
