Where Quantum Key Distribution Is Deployed in 2026

01Where quantum key distribution is deployed today

China runs the largest QKD network on the planet, and it isn’t close. The national system, called CN-QCN, stretches past 10,000 km of fiber through 145 backbone nodes, and it interconnects with the older Beijing–Shanghai backbone to push the combined mileage above 12,000 km.

Of those 145 nodes, 104 are trusted relays that pass keys hop by hop, and 41 are access points. Six ground stations link the fiber to the Jinan-1 quantum microsatellite, which extends reach between distant cities. It grew out of the 4,600 km satellite-ground network China reported in 2021, which used the earlier Micius satellite.

The system serves users in government and finance, with energy operators in the mix, though public reporting doesn’t name most of them. If you want proof that QKD can run at national scale, this is it. It also shows the cost of doing so. Those 104 relay sites are 104 boxes someone has to be trusted to run objectively.

02Europe is building EuroQCI

Europe’s push is coordinated under EuroQCI. All 27 EU member states have signed on, with national and cross-border projects at very different stages of build-out. Deutsche Telekom and AIT recently won an EU mandate to help build the quantum backbone.

The space segment centers on a prototype QKD satellite, EAGLE-1, whose launch has slipped repeatedly and now probably won’t happen before late 2027 or early 2028. A laser ground station for EAGLE-1 is part of that architecture. The EU’s stated aim has been a functional system around 2027, but with the satellite delayed and EAGLE-1 itself framed as a validation mission, that timeline no longer looks realistic. EuroQCI is real and funded, and it’s still mostly under construction.

03Switzerland: the long-running example

Switzerland has the longest track record. ID Quantique used a QKD system to secure Geneva’s election-result transmission in 2007, one of the earliest real-world quantum-cryptography installations anywhere, and the vendor said in 2017 that it was still protecting federal and cantonal votes.

On the finance side, ID Quantique and Mt Pelerin built a QKD-backed proof of concept in 2020 for a digital-asset custody system aimed at institutions. Geneva separately launched a 262 km quantum-network research platform in 2025. These protect the plumbing around private keys, the storage and the links. They don’t touch the on-chain signatures themselves.

04The UK opened QKD to commercial trials

BT and Toshiba run a quantum-secured metro network across London, with customers including the consultancy EY and the bank HSBC connecting over it in commercial trials. Access has been extended through Equinix data centers too. It’s a service used by customers, but BT still prefers calling it a trial.

05Asia beyond China

South Korea is working on the hardware. SK Telecom is developing photonic-integrated QKD meant to shrink bulky optics onto chips and, eventually, make them cheap to manufacture at semiconductor scale. Korean telecom and banking companies have also demonstrated QKD and post-quantum cryptography protecting communications between bank sites, a hybrid setup that stops short of a live production banking system.

Japan got there early. The Tokyo QKD Network has run since 2010 as a trusted-node testbed, an early example of the architecture later used in bigger networks.

06The United States hangs back

The US is the outlier. It has real activity: EPB in Chattanooga runs the country’s first commercially accessible quantum-network testbed, where companies and researchers can install and test quantum equipment on metro fiber. JPMorgan has done two things worth separating. One was a 2022 lab proof of concept in which QKD protected the data stream carrying its Liink blockchain application. The other was a 2024 project linking two of its data centers over deployed fiber with QKD-secured VPN tunnels.

07What today’s QKD deployments tell us

Put the deployments side by side and the shape is clear. QKD runs as high-value point-to-point links, built by governments and telecoms with a few banks alongside, and the long-distance ones lean on trusted nodes, though shorter direct links and some newer architectures don’t have to. It’s live and spreading. It’s also narrow. The loudest official skepticism comes from exactly two places: in the UK and the US, companies keep building QKD even as their national cyber authorities steer the highest-assurance systems toward post-quantum cryptography.

If you’re a crypto holder, the finance examples are the ones you should pay attention to. JPMorgan’s QKD protected the network traffic around a blockchain application, and Switzerland’s custody work protects key-storage and communication infrastructure, but neither makes an on-chain signature resistant to quantum forgery. That needs a quantum-resistant signature scheme, and QKD doesn’t provide one. The tool for that job is post-quantum cryptography. QKD is genuinely on the map now. It’s just not the thing standing between a quantum computer and your coins.

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QKD is on the map now. It’s just not the thing standing between a quantum computer and your coins.

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This article is educational and does not constitute security or investment advice.

// FAQ

Where is QKD actually deployed in 2026?

China runs the largest network (10,000+ km, 145 nodes). Europe is building EuroQCI, Switzerland has run QKD since 2007, the UK (BT–Toshiba) and US (EPB, JPMorgan) run trials and testbeds, and South Korea and Japan have hardware programs and testbeds.

Which country has the biggest QKD network?

China, by a wide margin. Its CN-QCN stretches past 10,000 km through 145 nodes, 104 of them trusted relays, and links to the Jinan-1 microsatellite.

Why do the UK and US hold back on QKD?

Their cyber agencies, the NCSC and NSA, steer the most sensitive systems toward post-quantum cryptography, citing QKD’s cost and its reliance on trusted relays. Industry still runs commercial trials.

Does any deployed QKD protect cryptocurrency?

Not the coins themselves. JPMorgan’s QKD protected network traffic around a blockchain app, and Swiss custody work protects key storage and links, but none makes an on-chain signature quantum-resistant. That needs post-quantum signatures.

Do these networks need trusted nodes?

Most long-distance ones do, because ordinary fiber can’t regenerate a quantum signal. Shorter direct links and some newer architectures (twin-field, MDI-QKD) avoid them.