Stripe's Tempo Payments Blockchain Opens to Public With Mastercard, UBS Onboard

Tempo, the stablecoin- and payments-focused blockchain from Stripe and Paradigm, launched its public testnet on Tuesday, enabling anyone to start building on top of the network. 

First announced in September, the Ethereum Virtual Machine-compatible network has been built to this point with early design input from global firms like OpenAI, Shopify, and Visa. On Tuesday, the Tempo team announced additional early partners, including Mastercard, UBS, and buy-now-pay-later firm Klarna—which recently announced plans for a stablecoin on Tempo.

“Tempo testnet is now open to anyone,” Tempo project lead and Paradigm founder Matt Huang posted on X. “It's been a pleasure working with great design partners to shape the chain: from teams moving billions across borders, to banks testing tokenized deposits, to AI companies exploring agentic flows.

With its testnet live, several key payments-specific features are now available—like dedicated payment lanes that guarantee blockspace and keep fees low, and stablecoin-native gas, which allows transactions to be paid for with USD-denominated tokens instead of a volatile, native blockchain token. 

"Working with Tempo allows Coastal to test and co-create the next generation of financial infrastructure,” Brian Hamilton, president of Washington-based design partner Coastal Bank, said in a statement posted to X.

“It’s not just about improving speed or efficiency—it’s about unlocking new capabilities for the broader ecosystem of fintech and embedded finance partners,” he added. “Together, we’re rethinking what modern banking can deliver.”

The network boasts microtransactions, global payments and remittances, agentic commerce, and tokenized deposits as out-of-the-box use cases. Additional features, like creating your own stablecoin from the browser, are also available. 

In its existing state, Tempo utilizes a rotating set of four validators operated by the team, but will look to bring in independent validators, as well as those from global partners and infrastructure providers as it approaches a mainnet launch. 

The network’s full rollout timeline has not yet been determined. 

In October, the network reportedly raised $500 million at a $5 billion valuation to propel its payments-focused blockchain. Around that time, it also added Dankrad Fiest, a top researcher from the Ethereum Foundation, to help build out the chain. 

Like Stripe with Tempo, USDC issuer Circle is working on its own stablecoin- and payments-focused blockchain, Arc. Its testnet went live in October with early participation from firms like Visa, BlackRock, and Goldman Sachs.