The Missing Piece for Onchain Payments

Global finance is moving onchain at a pace few are prepared to meet. Stablecoin monthly transaction volume hit $7.2 trillion in February 2026, nearly matching the US ACH network ($6.8 trillion) for the first time. ACH moves the vast majority of American salaries, yet stablecoins caught up to the incumbent technology’s volume in just over a decade.

The shift onchain is resetting baseline user expectations on price & speed. DEX aggregators routing USDC-to-EURC are beating leading remittance providers on price. A buyer in Mexico paying a merchant online in Berlin can complete payments directly from their wallet and settle in seconds. 3-5 business day settlement is quickly becoming a thing of the past.

The payments industry is already acting on this shift with Stripe’s recent acquisition of Bridge, Mastercard acquiring BVNK, and Visa's stablecoin settlement program running at a $4.5 billion annualized rate. All of these giants are making the same bet: volume follows faster, cheaper rails. The infrastructure providers who moved first are already capturing this B2B flow. Everyone else is watching their merchants move onchain and route around them.

A new class of payments is moving onchain

This shift takes two payment flows to the next level:

• Universal asset acceptance: Buyers pay in any token, and merchants settle in their preferred currency.
• Instant merchant settlement: Merchants get paid the moment the transaction clears.

Yet onchain payments require a capability traditional fiat rails take for granted: the merchant must receive the exact invoice amount.

The missing piece: guaranteed outputs

To support these use cases at scale you need a capability that’s taken for granted in traditional payments: the ability to guarantee the amount the merchant receives. In payments, the output is fixed. If the invoice is $500 the merchant expects to receive $500, not “approximately $500 depending on market conditions.”

Most swap infrastructure was built for trading, not payments. Traders sell a fixed amount and accepts what the market returns.

The problem is most crypto swap infrastructure wasn’t built this way. It’s built in the opposite direction: the user sets how much they want to sell and the output floats based on the market. This makes sense as the first primary use case for crypto was trading. Unfortunately this model doesn’t work for payments.

Turning any onchain asset into a guaranteed payment

This is the problem 0x solves with Exact Buy. 0x enables guaranteed-output swaps, where payment providers get exact merchant settlement without building the estimation, slippage handling, or fallback logic themselves. When combined with our advanced routing & deep onchain liquidity the result unlocks a truly advanced payments experience:

Turn any asset into a merchant payment. A merchant's preferred currency probably doesn't match what's in the user's wallet. Providers who are able to accept any asset a user holds expands potential payments & revenue from the stablecoin supply of $317B to the total cryptocurrency asset of supply of $2T+.

Settle in seconds, not days. Funds on traditional rails sit in processor and bank queues for days before merchants can use them. Onchain rails put funds in the merchant's wallet the moment the buyer pays, turning settlement delay into immediate working capital.

Evaluating swap infrastructure

Guaranteed outputs are table stakes, but they're not enough on their own. Any swap provider under evaluation should be pressure-tested to separate infrastructure built for payments from trading stacks retrofitted for the job. Five questions separate the two:

How 0x clears each one:

• 0x aggregates 520+ liquidity sources across 20+ major networks so the routing engine follows liquidity automatically as pools shift between venues.
• In a recent Enso study of 16 leading DEX aggregators, 0x ranked first with an industry-low 0.50% overquote rate and a near-zero 0.13% simulation revert rate, protecting checkout conversions.
• 0x Multi-Fee support lets integrators split the swap fee across multiple recipients in a single transaction. Funds settle atomically without manual post-trade reconciliation.
• Exact Buy launches across every EVM chain the Swap API supports, with new chains and Solana flowing through the same integration as they go live.
• 0x runs with 99.92% historical uptime and sub-250ms median response times, maintaining the stability required by regulated partners.

Execution as the differentiator

Merchants are already moving onchain. Providers whose infrastructure cannot clear onchain payments efficiently will watch them route elsewhere.

0x has powered onchain settlement since 2017, serving over 520 integrators including Coinbase Developer Platform, MetaMask, Phantom, Robinhood Wallet, and Trust Wallet. Cumulative swap volume has crossed $180 billion across 211+ million transactions. The infrastructure has been pressure-tested at the scale enterprise payments require.

Contact the 0x team to integrate Exact Buys into your payments stack.

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