The 8 Best Full-Stack Payment Processors in 2026

Running a business means collecting money, and collecting money means choosing a payment processor. The decision sounds simple enough until you start comparing options. Pricing models differ. Feature sets overlap in confusing ways. Some providers work better for online sales, others for in-person transactions, and a few claim to handle both equally well.

Full-stack payment processors bundle everything into one place. Gateway services, merchant accounts, fraud protection, reporting, and settlement all come from a single provider. This setup removes the headaches of coordinating between multiple vendors and reconciling data from separate systems. For small businesses and large enterprises alike, the appeal is obvious: fewer contracts, fewer dashboards, and fewer points of failure.

How Full-Stack Processors Differ from Traditional Setups

Traditional payment processing required separate relationships with a gateway provider, an acquiring bank, and often a third-party fraud service. Each vendor had its own contract, its own fee structure, and its own support team. When something went wrong, tracking down the source of the problem could take days.

Full-stack processors consolidate these functions. Authorization, settlement, dispute management, and compliance all run through one platform. The tradeoff is flexibility. Working with a single provider means accepting their way of doing things. For most businesses, the simplicity outweighs the constraints.

1. Finix

Finix began in 2016 as a company helping platforms become payment facilitators. Over the years, it built out a complete processing solution that businesses across the U.S. and Canada can use to accept payments online and in-store.

Visa, Mastercard, Discover, and American Express have certified Finix as a processor. Vanessa Colella, SVP and Global Head of Innovation and Digital Partnerships at Visa, noted that Finix is “moving payments technology forward by streamlining operations for platforms and payment facilitators.”

The platform supports credit and debit cards, ACH transfers, and digital wallets through a universal payments API. Transaction authorization, settlement, and dispute management all run through one system. Finix holds the highest level of security certification in the payments industry.

What makes Finix particularly useful for platforms is its customization. Businesses can choose from thousands of possible configurations and start transacting in as little as one day with as few as 3 API endpoints. The company offers managed merchant underwriting, allowing platforms to run white-labeled KYC, AML, and MATCH checks. Sub-merchant management helps keep compliance obligations handled for PCI, tax reporting, and sanctions screening.

Finix provides interchange-plus pricing, giving platforms greater control over processing fees. Real-time fraud monitoring, account updater technology, and automated reporting with more than 10 report types come embedded in the solution.

For marketplaces and SaaS providers, Finix handles efficient sub-merchant onboarding, recurring payments, subscription plans, and omni-channel support. Businesses with limited internal developer resources can use a brandable no-code/low-code solution that requires minimal integration work.

2. Stripe

Stripe remains one of the most recognized names in payment processing. As of October 2025, domestic card transactions cost 2.9% + $0.30, while international cards run 3.1% + $0.30 plus a 1.5% cross-border fee. ACH transfers cost 0.8%, capped at $5.

In-person payments through Stripe Terminal cost 2.7% + $0.05 per transaction. Manually entered cards cost 3.4% + $0.30, and international cards run 4.4% + $0.30.

Stripe supports more than 135 currencies across 195 countries. There are no setup fees, monthly fees, or hidden costs on the standard plan. Pricing is negotiable for high-volume merchants.

Starting June 17, 2025, Stripe introduced a $15 dispute counter fee charged when you contest a chargeback. Combined with the existing $15 dispute fee, each dispute carries a potential $30 cost. The counter fee is refundable if you win. Stripe also launched Smart Disputes, which uses AI to respond to chargebacks automatically with a 30% success fee on recovered amounts.

The technology is strong, though pricing sits around the industry average. Businesses processing large volumes can often negotiate better rates from direct processors.

3. Adyen

Adyen operates on a pay-as-you-go model with no monthly fees, setup costs, integration fees, or closure fees. The company uses Interchange++ pricing, which tracks interchange rates and scheme fees at the transaction level. This approach provides full visibility into what you pay for each payment.

The pricing structure includes a fixed processing fee, a scheme fee set by card networks, and a markup that typically runs around 0.6% per transaction. This model works best for large merchants with substantial volumes who can benefit from tailored rates and advanced reconciliation tools.

Adyen supports over 250 payment methods and operates in 35 countries. The platform includes acquiring services, meaning you work directly with Adyen rather than routing through intermediaries.

Security is solid. Adyen maintains PCI DSS Level 1 certification and has not reported any major public data breaches. The payment process includes tokenization, encryption, and behavioral analytics for real-time fraud detection. The company enhanced its RevenueProtect system with machine learning and AI-based pattern recognition.

Global brands including Uber, Spotify, and eBay use Adyen for their payment infrastructure.

4. Square

Square charges 2.6% + $0.10 per transaction for card-present payments including taps, dips, and swipes. Online store transactions cost 2.9% + $0.30, while keyed and manually entered transactions run 3.5% + $0.15.

In October 2025, Square introduced major pricing changes. All businesses now pay $0 (Free), $49 (Plus), or $149 (Premium) per month depending on their subscription tier. Online transactions on the Free plan increased to 3.3% + $0.30. Plus subscribers pay the previous rate of 2.9% + $0.30.

Square now accepts Bitcoin payments with 0% processing fees until December 31, 2026. After that date, the rate moves to 1%.

Custom pricing is available for businesses processing over $250,000 annually, based on volume, average ticket size, and seller history.

The platform operates in the U.S., UK, Australia, Canada, France, Ireland, and Spain. More than 4 million users rely on Square for their payment processing needs.

5. Checkout.com

Checkout.com is a London-based company that handles payment processing for enterprise clients in e-commerce, technology, and media sectors. The company functions as a payment gateway, acquirer, and processor.

Netflix, Pinterest, Vinted, Temu, Uber Eats, DocuSign, ASOS, Grab, Alipay, Alibaba, Shein, and Sony all use Checkout.com for their payment infrastructure. In 2025, the company signed an agreement with eBay to support its payment systems.

The company achieved profitability in 2024 with 45% revenue growth in core business segments. Leadership stated targets of 30% growth for 2025 while maintaining profitability.

Pricing is customized for each merchant with no intermediaries and no hidden fees. The company offers interchange-plus or flat-rate options. Checkout.com provides local acquiring capabilities in over 50 countries across Europe, North America, the Middle East, and Asia-Pacific. The platform supports more than 150 processing currencies, helping businesses avoid cross-border charges and reduce foreign exchange costs.

6. PayPal Braintree

Braintree functions as PayPal’s enterprise payment solution. Fees run 2.59% + $0.49 per transaction for credit, debit, and digital wallets. The service is available in the United States, Canada, Australia, Europe, Singapore, Hong Kong, Malaysia, and New Zealand.

Standard credit and debit card transactions cost 2.9% + $0.30. There are no monthly or setup fees. Braintree does not charge extra for accepting PayPal, Venmo, Apple Pay, or Google Pay.

Custom flat rates, interchange-plus pricing, and discounted rates are available for established businesses based on their model and processing volume.

Braintree processes over $50 billion annually and handles more than 1 billion transactions per quarter.

Customers sign up on a month-to-month basis with no lengthy contracts or early termination fees. There are no PCI compliance fees or minimum transaction requirements beyond the flat per-transaction cost.

7. Worldline

Worldline is a European-headquartered payments processor with teams across acquiring, issuing, and acceptance. The company has a strong footprint in multi-country commerce.

The core offering includes acquiring and processing services that help businesses launch in new markets without rebuilding local infrastructure. Omnichannel acceptance options reduce channel-specific workstreams.

Implementation programs allow businesses to reach first value in 4 to 12 weeks depending on scope. For companies expanding across borders, Worldline provides operational scale without requiring an entirely new payments stack in each region.

8. Airwallex

Airwallex focuses on international payments and currency management. The platform offers like-for-like settlement in more than 14 currencies, meaning businesses can receive funds and hold them in the same currency without forced conversions or hidden FX margins.

Businesses can create local currency accounts in minutes and receive local bank details in 60+ countries. This setup lets companies accept payments as if they were local businesses in major markets.

Real-time FX is available with interbank rates on more than 60 trade currencies, with 100+ currencies priced live on the spot market. Airwallex claims businesses can cut FX costs by up to 80% compared to traditional banks.

Global payouts reach 200+ countries, with 120+ using local rails. Over 90% of transfers use local payment rails, with about 95% arriving within hours or the same day and around 57% arriving instantly.

Full-Stack Payment Processors Comparison

What to Consider Before Choosing

Transaction volume matters. Processors like Adyen and Checkout.com work best for high-volume merchants who can negotiate favorable rates. Helcim and Square serve smaller operations with more predictable pricing.

Geographic reach varies. If you sell in multiple countries, look at where each processor has local acquiring capabilities. Local acquiring reduces cross-border fees and improves authorization rates.

Integration complexity differs. Stripe and Finix offer robust APIs for developers. Square provides plug-and-play solutions for businesses without technical resources.

Dispute handling costs add up. Stripe’s new $30 potential dispute cost is worth noting if your business sees frequent chargebacks. Other processors have their own fee structures for disputes.

Pricing models affect margins. Interchange-plus pricing tends to favor high-volume merchants. Flat-rate pricing offers predictability for smaller operations but can cost more as volume grows.

Final Thoughts on Making the Right Choice

Payment processing costs will always be part of running a business, but the right processor can turn those costs into a source of efficiency rather than frustration. The 8 options covered here represent different approaches to the same problem: how to move money reliably while keeping fees reasonable and compliance handled.