B2B payments are how one business pays another, and in 2026 that means five rails a treasury team actually has to choose between: ACH, wire, RTP or FedNow, commercial cards, and stablecoins. In 2025 the ACH Network alone moved 8.08 billion business-to-business payments worth $63.11 trillion, up 9.9% and 8.4% year over year respectively (Nacha). This guide covers each rail, the vendor landscape, a worked cross-border payout example with fees, a decision framework, and where stablecoin rails fit next to the fiat ones.
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B2B payments describes any money movement from one business to another: paying suppliers, settling invoices, disbursing to contractors, moving cash between corporate entities, or funding merchant payouts on a platform. The rail choice depends on speed, cost, geography, transaction size, and who holds the ledger. B2B is the largest single category in most US rails: 8.08 billion payments and $63.11 trillion moved over the ACH Network in 2025, and B2B is the Network's fastest-growing segment (Nacha). Software has changed which rail a given payment uses more than the rails themselves have changed. That is why this guide is organized by rail first and vendor second.
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Every B2B payment in the US goes over one of five rails. Each was built for a different job, has a different cost curve, and settles on a different clock. Picking the right rail for a given payment is the treasury decision that matters most. Vendors ride on top of the rails; the rails set the physics.
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ACH is the batch-processing rail that carries payroll, vendor payments, and most recurring B2B flows in the US. Standard ACH settles in one to two business days, Same Day ACH settles the same business day within defined windows, and per-transaction cost to the originator is typically pennies rather than dollars. Volume tells the story: the ACH Network moved 35.19 billion payments worth $93 trillion in 2025, of which 8.08 billion payments and $63.11 trillion were B2B, and Same Day ACH grew 16.7% in volume and 21.4% in value year over year (Nacha). ACH is the default answer for scheduled US-to-US business payments where instant settlement is not required.
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Wire transfers are real-time gross settlement for high-value or time-sensitive payments. Fedwire Funds Service is the Federal Reserve's electronic funds-transfer service that banks, businesses, and government agencies use for same-day transactions with the finality of payments credited to Federal Reserve Bank master accounts (Federal Reserve). Wires are the rail of record for M&A closings, treasury movements, and international payments where the recipient needs certainty of receipt today. The tradeoff is fee: sending banks typically charge $15 to $35 per outgoing wire (Wise, for context, positions its own wire cost against the "$25+ fee typically charged by U.S. banks" in its business pricing, Wise Business). Cross-border wires additionally route over SWIFT, add correspondent banks, and can take one to three business days end to end.
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The RTP network from The Clearing House and FedNow from the Federal Reserve are the two US real-time payment rails. RTP has cleared and settled over 1.7 billion transactions worth over $3.2 trillion since 2017, supports transactions up to $10 million, ran 142 million transactions worth $576 billion in Q2 2026 alone, and has over 1,322 participating financial institutions as of July 2026 (The Clearing House). FedNow is the Federal Reserve's instant-payments service, launched to give financial institutions of every size a way to deliver 24/7/365 payments to their customers (FedNow Service). Both rails carry ISO 20022 messaging with rich remittance data attached, which is why they are gaining traction for B2B use cases like supplier payouts, insurance disbursements, and merchant settlement. Instant rails cost more per transaction than ACH and less than wires; they are the right choice when settlement finality inside sixty seconds is worth paying for.
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Corporate cards, purchasing cards, and virtual cards run over the Visa and Mastercard networks and settle to the issuer's sponsor bank on card-network cycles. The buyer gets rebates or cashback and terms on the card statement, the seller gets funds in a day or two net of interchange, and the platform gets a real-time authorization stream it can control with spend policies. Ramp is the archetype of the modern B2B card program: it pays out over ACH, card, check, and international wire in USD or foreign currencies inside a single spend platform used by more than 70,000 businesses (Ramp Bill Pay). Cards are the right rail for buyer-side discretionary spend, subscription payments, and any B2B flow where the buyer wants deferred settlement or rewards and the seller is willing to accept interchange.
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Stablecoin rails move dollar-denominated value across blockchains without touching ACH, wire, or card networks. Circle's Cross-Chain Transfer Protocol enables native USDC to move 1:1 between chains through a burn-and-mint mechanism, with Fast Transfer for faster-than-finality settlement and Hooks for automated post-transfer actions across Arbitrum, Avalanche, Base, Ethereum, Solana, Polygon, OP Mainnet, Unichain, and roughly two dozen other chains (Circle CCTP). Stripe completed its acquisition of Bridge in February 2025 to fold stablecoin infrastructure into its platform for global money movement (Stripe). Stablecoin rails settle in seconds to minutes, run 24/7, and are usually the cheapest rail for a cross-border B2B payment once fiat off-ramp costs are included; they are the newest of the five and the one where product surfaces are moving fastest.
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Vendors package one or more rails behind an API or dashboard with the compliance, reconciliation, and workflow a finance team needs. The right vendor depends on which rails the business needs, whether it wants a payment service provider that also holds the bank contract, or a payments platform that connects to the business's own bank. The comparison below is by rail coverage and product model, not by brand preference.
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The clearest way to compare B2B rails is to run one payment across each of them. Scenario: a US SaaS company owes a contractor in the Philippines $8,000 for a month of work, due within seven days, delivered in USD or the peso equivalent. The payer is a US LLC with a Wise Business account, a corporate bank, and a stablecoin-capable wallet. The recipient can accept USD wires, Wise local delivery in PHP, or USDC to a self-custody wallet.
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Bank wire. The US corporate bank charges an outbound international wire fee, typically $25 to $50, and typically spreads the FX rate from the mid-market rate. The wire routes over SWIFT via one or more correspondent banks, and each intermediate can deduct a lifting fee. End-to-end delivery is one to three business days. All-in cost from the payer's side sits at roughly $60 to $200 on an $8,000 principal by the time FX spread is included. Wire is the answer only when the recipient's bank cannot accept anything else.
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Wise Business. Wise sends wires at the mid-market rate with no FX markup and prices its own transfer fee as low as $1.13, versus a "$25+ fee typically charged by U.S. banks," and delivers 96% of payments in under 24 hours (Wise Business). For $8,000 USD to PHP the payer typically pays a percentage-based Wise fee in the low tens of dollars, plus a small fixed component, and the contractor receives PHP into a local bank account in under a day. All-in cost sits in the tens of dollars, roughly one order of magnitude cheaper than the bank wire.
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Stablecoin (USDC via Circle CCTP). The payer converts $8,000 USD to USDC at an on-ramp, sends USDC to the contractor's wallet address, and the contractor either holds USDC, converts to PHP at a local off-ramp, or spends USDC directly. Circle CCTP has no on-chain fee for a standard USDC transfer, with fees for Fast Transfer and Hooks published per chain (Circle CCTP). End-to-end network cost on-chain is typically dollars, not tens of dollars, and settlement is minutes. The variable cost is the fiat off-ramp on the recipient side, which depends on the local provider. For a self-employed contractor paid in USDC monthly, this is usually the cheapest rail; for a corporation that needs the money in a bank account, wire or Wise usually wins after off-ramp friction.
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Domestic-only rails don't fit this scenario. ACH is US-only. RTP and FedNow are US-only and have transaction caps ($10 million on RTP). Cards work if the contractor accepts card payments, but the seller pays interchange, so most contractors prefer bank or crypto delivery.
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The pattern generalizes. For a US-to-US recurring vendor payment under $1 million, ACH wins on cost. For a US-to-US instant payment inside sixty seconds, RTP or FedNow wins. For US-to-international where the recipient has a bank account and speed matters, Wise or a modern PSP wins. For US-to-international where the recipient can hold digital dollars, or for treasury movement across chains, stablecoin rails win.
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Ranking vendors before answering these usually leads to a bad fit that the finance team discovers six months in. Answer these five first, then pick the vendor whose model matches.
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1. Which rails does this payment need? ACH for scheduled US-to-US flows. Wire or RTP or FedNow for instant. Cards for buyer-side discretionary spend. Stablecoins for cross-border or on-chain. Most businesses need at least three of the five.
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2. Domestic or cross-border, and in which corridors? A US-only vendor list looks very different from one that has to move USD to PHP, MXN, EUR, and BRL every month. Wise, Modern Treasury, and stablecoin rails all handle cross-border differently.
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3. Who holds the bank contract? Full-service payment service providers like Modern Treasury sit between the business and the bank, so onboarding is faster. Direct-bank models keep the business in contract with its own bank, so deposit economics are better. The right answer depends on volume.
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4. What's the accounting integration surface? Ramp and BILL both sync deeply with QuickBooks, NetSuite, Xero, and Sage Intacct. A B2B payments vendor that does not sync to the accounting system creates monthly reconciliation debt.
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5. What settlement clock does the recipient care about? The wrong end of this question is the payer's convenience. The right end is what the seller, contractor, or supplier needs to hear "paid" and stop chasing. Instant rails and stablecoins are usually the answer for anyone tired of waiting on wires.
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Stablecoins are one of the five B2B payment rails, not a replacement for the others. The honest positioning is: for cross-border payments where the recipient can hold digital dollars, and for treasury movement between corporate wallets across chains, stablecoins are cheaper and faster than the fiat rails. For US-to-US recurring vendor payments they cost more than ACH once off-ramp is included. For high-value instant US settlement, RTP and FedNow are usually simpler than orchestrating a stablecoin transfer plus off-ramp.
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Three product surfaces cover most of the practical use cases. Circle CCTP is the permissionless protocol layer, with Fast Transfer and Hooks and 25+ supported chains for developers integrating USDC into apps, bridges, and wallets (Circle). Stripe folded Bridge into its platform in February 2025, putting stablecoins on the same API surface Stripe already offers for cards and ACH (Stripe). Modern Treasury also offers stablecoin orchestration inside the same API it uses for ACH, wire, RTP, FedNow, and push-to-card, so a business already on Modern Treasury can add stablecoins without a second vendor (Modern Treasury). For a business already picking a B2B payments vendor, the practical question is whether stablecoins ride on the same API as the fiat rails or need a separate integration.
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For US-to-US scheduled payments, ACH is the cheapest at pennies per transaction (Nacha). For cross-border payments where the recipient can accept digital dollars, stablecoins are typically the cheapest once off-ramp is included, with no on-chain fee for standard USDC transfers over CCTP (Circle).
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Both are US real-time payment rails carrying ISO 20022 messaging. RTP is operated by The Clearing House and has been live since 2017, with over 1.7 billion transactions and $3.2 trillion cleared (The Clearing House). FedNow is operated by the Federal Reserve and is designed to give every financial institution, including community banks and credit unions, a way to deliver 24/7 payments (FedNow). Many participating banks connect to both.
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Same Day ACH has a per-transaction cap of $1 million as of 2023, and standard ACH has no per-transaction cap set by Nacha though originating banks impose their own limits (Nacha). For payments above these thresholds most treasuries move to wire.
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Yes, businesses can accept and send USDC and other US-dollar stablecoins in the US, and Stripe's completed acquisition of Bridge in February 2025 folded stablecoin infrastructure into its regulated platform for global money movement (Stripe). State-level money transmission and federal Bank Secrecy Act requirements still apply, and businesses generally work with a compliant on-ramp and off-ramp partner rather than handling crypto custody themselves.
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Both automate AP with OCR, approval workflows, and accounting-software sync. Ramp bundles AP with corporate cards and an AI-powered spend platform used by more than 70,000 businesses, with core Bill Pay features on a free tier (Ramp Bill Pay). BILL is a standalone AP automation product with deep accounting-firm distribution (BILL). Teams that already want a corporate card program usually pick Ramp; teams whose accountant runs on BILL usually stay on BILL.
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A full-service PSP like Modern Treasury handles the bank relationship, KYB, and compliance, so a platform can go live in days rather than months (Modern Treasury). The tradeoff is deposit economics and negotiating room. Modern Treasury also supports a bring-your-own-bank model, so a business can start on the PSP and migrate to direct-bank relationships as it scales without rebuilding the integration.
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International payment gateway explained walks through vendor pricing and a worked example.
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