Opayo vs. Stacks Comparison Chart

NMI Payments is an embedded payments solution that lets SaaS platforms, Software companies and ISVs integrate, brand, and manage payment acceptance directly within their software—without becoming a PayFac or building complex infrastructure. As a full-stack processor, acquirer, and technology partner, NMI handles onboarding, compliance, and risk so you can stay focused on growth. The modular, white-label platform supports omnichannel payments, from online, mobile and in-app to in-store and unattended. Choose from full-code, low-code, or no-code integration paths and launch in weeks, not months. Built-in risk tools, flexible monetization, and customizable branding help you scale faster while keeping full control of your experience. With NMI’s developer-first tools, sandbox testing, and modern APIs, you can embed payments quickly and confidently.

Accept every payment quickly, easily, and securely. Easily accept card payments—no matter if you’re selling on the go or at your store. Streamline the way you create, send, and track your invoices. Customer not there in person? Take remote credit card payments over the phone or from your computer, and get paid fast. Create and grow your online store, and seamlessly accept online payments with Square. We make accepting cards as fast, painless, and secure as possible. There are no extra fees, no long term contracts, and no tricks. Just fast, secure payments you can depend on.

EBizCharge is the leading embedded payments application for businesses to accept payments directly inside QuickBooks, Microsoft Dynamics, NetSuite, SAP, Acumatica, and 100+ other business systems. Trusted by 20,000 companies and voted best fintech solution by the Globee® Awards, EBizCharge combines modern billing tools with integrated payment processing to help B2B companies get invoices paid faster, eliminate manual work, and keep payment data automatically synced to their ERP. Companies use EBizCharge to: ◉ Accept credit card, debit card, and ACH payments natively in their ERP, CRM, or shopping cart ◉ Automate billing and reconciliation to save time and reduce errors ◉ Speed up collections with easy billing tools: payment links, online customer portal, recurring billing, saved cards, and more ◉ Reduce risk with enterprise-grade security certified by the PCI-Security Council: PCI-compliance, encryption, and tokenization

PayKings is a merchant account provider that helps businesses secure payment processing services in industries often rejected by traditional payment processors. The platform offers merchant accounts, payment gateways, and payment processing solutions designed to support businesses with specialized risk profiles. What is a high risk merchant account? A high risk merchant account is a payment processing account for merchants that are classified in a high risk category. They require high risk credit card processing solutions. The PayKings Team can get you approved today for a low to high risk merchant account for B2B, eCommerce, or Retail at reduced rates and fees. Credit repair merchant accounts are essential for companies in the credit repair space. You provide credit solutions to your customers and we’ll take care of the payment processing. Selling any type of merchandise through an ecommerce store has its risks.

Square POS is a simple and intuitive point-of-sale (POS) solution that delivers a robust set of tools for sales tracking, inventory, online payment processing, digital receipts, and analytics. Available for Android and iOS devices, Square POS provides a recording of transactions offline by storing data locally and then automatically syncing all information when their is an Internet connection. Additionally, Square POS enables users to seamlessly manage details, such as names, prices, and quantities and provides features such as a barcode scanner, discounts, credit card processing, gift cards, refunds, and more. Whether or not your business has a brick-and-mortar location, building a robust online presence can help you engage customers from a distance. Square’s online solutions work with any of the above point-of-sale systems, or you can use them on your own. We give you the tools to create thumb-stopping, compelling, and on-brand ads that perform.

Convesio is a next-generation hosting and payment platform built to help commerce businesses grow faster, smarter, and more securely. Designed for WordPress and WooCommerce, Convesio combines high-performance hosting with an integrated payment ecosystem — ConvesioPay — that streamlines how merchants accept, process, and manage transactions online. With ConvesioPay, businesses get access to fast, secure payment processing that’s deeply connected to their hosting environment. This means lower latency, fewer plugin conflicts, and real-time visibility into revenue performance — all from a single dashboard. Combined with Convesio’s scalable container-based hosting, built-in caching, and advanced uptime management, the result is an optimized foundation for conversion, reliability, and growth. From startups to enterprise-level ecommerce operations, Convesio empowers merchants to focus on selling — not managing servers or chasing integrations.

Melio is an accounts payable tool built to simplify bill payments, boost workflow efficiency, and optimize cash flow for businesses of all sizes. To get started, try all of Melio's features free for 30 days! Pay vendors online through bank transfers or credit/debit cards, even if they typically accept checks—Melio manages the manual work for you. Effortlessly integrate with QuickBooks and Xero to ensure your financial records stay current. With Melio, pay by bank transfer or card to extend cash flow and earn rewards. Adding vendor or bill details is a breeze—input them manually, upload files, or take a photo of invoices. Schedule payments to align with your cash flow, and let Melio handle the rest. International vendor payments are made easy by paying in their local currency for products and services your business needs. The Melio mobile app, available for iOS and Android, lets you monitor and manage payments anytime, giving you full control over your finances on the go.

Fraudnet's AI-driven platform empowers enterprises to prevent threats, streamline compliance, and manage risk in real-time. Our sophisticated machine learning models continuously learn from billions of transactions to identify anomalies and predict fraud attacks. Our unified solutions: comprehensive screening for smoother onboarding & improved compliance, continuous monitoring to proactively identify new threats, & precision fraud detection across channels and payment types. With dozens of data integrations and advanced analytics, you'll dramatically reduce false positives while gaining unmatched visibility. And, with no-code/low-code integration, our solution scales effortlessly as you grow. The results speak volumes: Leading payments companies, financial institutions, innovative fintechs, and commerce brands trust us worldwide—and they're seeing dramatic results: 80% reduction in fraud losses and 97% fewer false positives. Request your demo today and discover Fraudnet.

Revaly is a Payment Performance Management platform designed to ensure that every legitimate transaction succeeds, protecting the recurring revenue businesses depend on. It uses exclusive issuer signals, network intelligence, and AI-powered optimization to maximize payment approvals across the entire lifecycle. By preventing avoidable failures at the first attempt and intelligently recovering declined payments, Revaly reduces involuntary churn and strengthens customer relationships. The platform continuously analyzes routing errors, behavioral patterns, and ecosystem signals to turn unpredictable payments into predictable revenue. Subscription-based companies rely on Revaly to lift approval rates and compound revenue growth without disrupting their existing billing stack. With over 100 integrations, the system fits seamlessly into current workflows while delivering measurable, long-term financial impact.

Gr4vy's no-code payment orchestration platform empowers enterprises with full control to automate, customize, and optimize their payment strategy. Through a single integration, businesses can access +400 payment methods, anti-fraud tools, and payment service providers, enabling them to optimize their stack in just a few clicks, all in a centralized platform. While a PSP is incentivized to route transactions through its own infrastructure, Gr4vy remains agnostic. Built on dedicated cloud instances, Gr4vy infrastructure is the only one that eliminates the risk of a single point of failure, ensuring redundancy and high performance. As the only orchestrator with edge computing, all data and transactions are separate from others, minimizing the risk of a data breach, providing data sovereignty, reducing latency, and increasing efficiency. Gr4vy future-proofs payment stacks with flexibility, scalability, simplicity, and innovation—enhancing performance along the way.