Stripe-backed Tempo taps Mastercard, UBS for public testnet debut

Stripe-backed Tempo blockchain launches public testnet with Mastercard, Klarna, UBS and Kalshi, targeting sub-cent stablecoin payments for mainstream finance.

Tempo, a payments-focused blockchain backed by Stripe and crypto investment firm Paradigm, launched its public testnet, the company announced, marking a step in its effort to enable stablecoin payments for mainstream financial use.

The launch allows developers and enterprise partners to test payment flows on-chain, moving the project from concept into live network experimentation, according to the company.

Tempo and Stripe strike deal

First introduced in September, Tempo was designed for high-volume financial transactions. The testnet enables fintech firms, banks, and developers to test the network’s performance ahead of a future production launch.

Tempo announced an expansion of its partner group alongside the testnet debut. New participants include buy-now-pay-later company Klarna, prediction markets platform Kalshi, payments company Mastercard, and Swiss bank UBS. They join an earlier group of design partners including Deutsche Bank, Visa, Shopify, OpenAI, and Nubank. The roster spans traditional banking, global card networks, commerce platforms, artificial intelligence, and digital-native consumer finance.

Tempo targets obstacles that have limited blockchain adoption in everyday payments, including network congestion, volatile transaction fees, and dependence on native gas tokens with unpredictable pricing. The network charges approximately one-tenth of a cent per transaction, with fees paid in U.S. dollar-denominated stablecoins, according to the company.

By eliminating exposure to a volatile gas token, Tempo offers a predictable cost structure for enterprise-scale payment flows, the company stated. The network also provides instant finality, a feature considered essential for real-time checkout, remittances, and time-sensitive financial transactions. The testnet will serve as a testing ground for those technical claims, allowing participants to assess throughput, reliability, and integration complexity under live conditions.

Tempo’s launch comes as stablecoins transition from crypto trading tools into financial infrastructure. Stablecoins represent approximately $300 billion in assets and are increasingly used for cross-border payments, treasury operations, and merchant settlement.

A recent report from Keyrock and Bitso projects that business-to-business payments, peer-to-peer transfers, and card-based transactions will be the primary growth engines for stablecoins in coming years. Demand for programmable, dollar-denominated settlement continues to rise as global payments become more digital, according to the report. That momentum has fueled new blockchains and infrastructure platforms built around stablecoin payments, putting Tempo into competition with other settlement networks.

The testnet launch signals Stripe’s expansion in the stablecoin economy. Through its stablecoin-focused subsidiary, Bridge, Stripe has been building infrastructure to support digital dollar issuance and global settlement. Bridge is expected to help Klarna issue its own digital dollar next year, connecting consumer financing to blockchain-based payment rails. The strategy positions stablecoins as a foundational layer for internet-native payments, according to industry observers.

Tempo’s path from testnet to large-scale production use remains uncertain. The network must demonstrate that its low-fee model and instant finality can scale reliably under sustained transaction volumes. Network stability, security, uptime guarantees, and regulatory compliance will be scrutinized as banks and global payment firms evaluate integration.

Regulatory clarity will be critical as traditional financial institutions move on-chain. As the lines blur between blockchain-native infrastructure and regulated payment systems, projects like Tempo will be tested on performance, governance and compliance.

With backing from Stripe and Paradigm and a network of global partners, Tempo enters this phase with institutional support. The launch of Tempo’s public testnet comes as stablecoins expand into mainstream commerce and competition intensifies to define the dominant infrastructure for on-chain payments.