How we make this list: we compare pricing pages, product documentation and public user reviews. Rankite is independent; if a vendor ever pays for a featured spot, that listing is clearly labeled Partner.
Key takeaways
- Stripe and Square are the safe defaults for most small businesses: no monthly fees, published rates, and you can be live the same day.
- Authorize.net's $25 monthly fee looks like a drawback until your volume crosses roughly $2,500 to $3,000 a month, at which point its lower per-transaction cost starts winning.
- Helcim is the standout for growing businesses that want interchange-plus pricing without negotiating: no monthly fee, and the margin shrinks automatically as volume grows.
- Adyen, Checkout.com and Worldpay are built for scale and global reach, with quote-only pricing that only makes sense once volume justifies the sales process.
- PayPal converts well because buyers trust it, but its card and wallet fees run higher than Stripe's, so run the numbers on your average order value before defaulting to it.
Quick comparison
| Tool | Best for | Starting price | Free plan |
|---|
 Stripe | developers and online-first businesses | 2.9% + 30¢ per successful transaction (domestic cards) | No |
 Square | businesses selling in person and online together | 2.9% + 30¢ per online transaction | Yes |
 PayPal | checkout conversion through buyer trust | 2.89% + 29¢ per transaction (card processing) | No |
 Authorize.net | established businesses that want a classic gateway | $25 per month + 2.9% + 30¢ per transaction (all-in-one) | No |
 Adyen | enterprises and global commerce | See website | No |
 Braintree | developers who want PayPal in the checkout mix | See website | No |
 Checkout.com | online businesses obsessed with payment performance | See website | No |
 Helcim | growing businesses that want interchange-plus without haggling | Interchange Plus, no monthly fee | No |
 Worldpay | scale, omnichannel retail and platforms | See website | No |
Is your product missing or out of date?
We review this list regularly. Vendors can request a listing, send updated pricing or ask about featured placement.
The best payment gateway software
Starting price2.9% + 30¢ per successful transaction (domestic cards)
Free planNo
Stripe is the default answer for online payments for a reason. The API is the product: clean, well-documented and surrounded by libraries, prebuilt checkout pages and billing tools that handle subscriptions, invoicing and tax. A developer can accept a first payment in an afternoon, and the dashboard covers the no-code needs like payment links and manual invoicing.
The pricing is simple, which is both the appeal and the trap. At 2.9 percent plus 30 cents per domestic transaction, with no monthly fee, small businesses know exactly what they pay. But simple is not cheap at scale: once you process serious volume, interchange-plus pricing from a provider like Helcim or Adyen undercuts the flat rate meaningfully. Stripe knows this and offers custom volume pricing, but you have to ask.
What we like- The best developer experience in payments, with documentation and tooling for everything
- Supports 135-plus currencies and payment methods
- No setup fees, monthly fees or hidden fees
Watch out for- Flat-rate pricing gets expensive at high volume compared with interchange-plus
- Risk reviews can temporarily hold payouts
- Premium support costs extra
Starting price2.9% + 30¢ per online transaction
Free planYes
Square owns the "sell anywhere" position. The free plan bundles a point-of-sale app, an online store, invoicing, appointments and banking basics for $0 a month, and you only pay when you take a payment. For a cafe, salon, boutique or food truck, that removes the entire payments project: buy a $59 reader, download the app, start selling.
Online, Square charges 2.9 percent plus 30 cents, matching Stripe's headline rate. The ecosystem is the differentiator: inventory, staff management, marketing and loans all live in one place, which is convenient until it is not. Businesses that outgrow the flat rate can move to Square Plus or Premium for lower processing fees, or talk to the sales team above $250,000 a year.
What we like- Free plan starts at $0 with POS, online store, invoicing and booking included
- One system for in-person and online sales
- Deep hardware ecosystem from $59 readers to full registers
Watch out for- Flat-rate pricing like Stripe, so volume discounts need a custom plan
- Account holds during risk reviews are a common complaint
- Advanced POS features require Plus or Premium plans
Starting price2.89% + 29¢ per transaction (card processing)
Free planNo
Nobody doubts PayPal's conversion power. Offering the PayPal button at checkout lifts completion rates because buyers trust the brand and like the buyer protection, and the company's own research has long claimed a large conversion lift. Card processing starts at 2.89 percent plus 29 cents, with in-person tap-to-pay at 2.29 percent plus 9 cents.
The math deserves a spreadsheet, not a habit. PayPal Checkout's card rate is 2.99 percent plus 49 cents, and wallet payments run 3.49 percent plus 49 cents, both richer than Stripe's flat rate. For high-trust, low-consideration purchases the conversion lift can still pay for itself. For everyone else, PayPal works best as an additional payment option alongside a primary gateway, not as the only one.
What we like- More than 430 million active accounts, so buyers check out with confidence
- No monthly fee on standard accounts
- Seller protection on eligible transactions
Watch out for- Card rates run slightly higher than Stripe's headline rate
- PayPal and Venmo wallet payments cost 3.49% plus 49 cents
- New accounts face holds and rolling reserves
#4
Authorize.net
Best for: established businesses that want a classic gateway
Visit authorize.net
Starting price$25 per month + 2.9% + 30¢ per transaction (all-in-one)
Free planNo
Authorize.net has processed online payments since the dial-up era, and its pitch in 2026 is refreshingly direct: lower per-transaction costs than PayPal, with the math to prove it. The all-in-one plan runs $25 a month plus 2.9 percent and 30 cents per online transaction, and the company publishes the breakeven against PayPal at around 89 transactions a month.
The interesting option is "gateway only": skip Authorize.net's bundled processing, connect your own merchant account, and negotiate interchange-plus pricing that often lands near 2.2 to 2.5 percent effective. That flexibility is something PayPal and Stripe do not offer at list price. The trade-off is old-school texture: a $25 monthly fee, a less modern dashboard, and a signup flow that feels like enterprise software.
What we like- Long-trusted brand now backed by Visa
- Gateway-only option lets you pair it with your own merchant account and negotiate interchange-plus
- Free 24/7 human support
Watch out for- The monthly fee penalizes very low volume
- The interface and onboarding feel dated
- The all-in-one rate is not the cheapest available
Starting priceSee website
Free planNo
Adyen is the gateway behind many of the world's largest retailers and platforms, processing over a trillion euros a year. The value proposition is unified commerce: one integration, one contract and one reconciliation flow for cards, local payment methods, in-person terminals and payouts across dozens of markets. Pricing is interchange-plus, so you see the real card-network cost plus Adyen's markup, with no blended-rate mystery.
Everything about the buying experience signals enterprise. Pricing is quoted, minimums apply, and onboarding runs through a sales team. For a mid-market company selling internationally, Adyen can genuinely lower the effective rate while improving authorization rates across borders.
What we like- One platform for online, in-person and marketplaces across 150-plus currencies
- Interchange-plus pricing with full cost transparency
- Proven at enormous scale with trillions in annual volume
Watch out for- Quote-only pricing with minimum invoice thresholds
- Sales-led onboarding, no self-serve signup
- Far more platform than a small merchant needs
Starting priceSee website
Free planNo
Braintree has long been the developer-friendly way to accept PayPal alongside cards, and buyers should know the brand is now folding into PayPal Enterprise Payments. The product itself remains: a single API and SDK set covering cards, PayPal, Venmo, Apple Pay, Google Pay and local methods, with a sandbox that lets developers test the full payment flow without touching real money.
For marketplaces and platforms, the appeal is PayPal's buyer network combined with proper developer tooling and straightforward PCI handling through hosted fields and drop-in UI. The honest caveats are the rebrand, which means documentation and naming are in flux, and the sales-led pricing, which replaced the old published rates.
What we like- One integration for cards, PayPal, Venmo, Apple Pay and Google Pay
- Full-featured sandbox for testing before going live
- Level 1 PCI compliance with drop-in UI options
Watch out for- The brand is transitioning into PayPal Enterprise Payments, which creates confusion
- Pricing is quote-based
- Enterprise support runs through PayPal channels
#7
Checkout.com
Best for: online businesses obsessed with payment performance
Visit checkout.com
Starting priceSee website
Free planNo
Checkout.com sells one thing above all: more of your payments succeeding. Its Intelligent Acceptance engine tunes routing, retries and authentication per transaction, and the company reports meaningful acceptance-rate uplifts for merchants like eBay, Uber and Spotify. With local acquiring across 50-plus countries and support for 150-plus processing currencies, it is built for cross-border e-commerce at scale.
This is unapologetically an enterprise product. There is no published pricing, no self-serve signup and no small-business tier; you talk to sales, you scope the integration and you negotiate.
What we like- Intelligent Acceptance uses AI to lift authorization rates
- Processed $300 billion for enterprise merchants in 2025
- Local acquiring in more than 50 countries
Watch out for- Enterprise focus with quote-only pricing
- No self-serve path for small merchants
- Getting value from the optimization tools needs technical resources
#8
Helcim
Best for: growing businesses that want interchange-plus without haggling
Visit helcim.com
Starting priceInterchange Plus, no monthly fee
Free planNo
Helcim's pitch is disarmingly simple: pay the wholesale card cost plus one transparent markup, with no monthly fee, and watch the markup shrink automatically as your volume grows. No negotiation, no rep to call, no "call us for better rates" dance. The company even pays up to $500 in processing credits and migrates your customer card data free if you switch from a competitor.
For a business crossing that $5,000-a-month line where interchange-plus beats flat rate, Helcim is the easiest way to capture the savings. The statements show the real interchange cost, which is educational the first time you see how much of your Stripe bill was markup. The trade-offs are real too: variable monthly bills demand more bookkeeping attention than a flat rate, the app and integration ecosystem is narrower, and coffee-shop ticket sizes may do better on flat pricing.
What we like- No monthly fees, setup fees or cancellation fees of any kind
- Volume discounts apply automatically as you grow
- Free data migration plus switching credits
Watch out for- Interchange-plus bills are harder to predict than flat rates
- The integration ecosystem is smaller than Stripe or Square
- Very small tickets can cost more than on flat-rate plans
Starting priceSee website
Free planNo
Worldpay is one of the largest payment processors on earth, and its homepage courts three audiences at once: small and mid-sized businesses, enterprises and software platforms embedding payments. The scale brings real advantages: global acquiring, smart routing and retries, fraud screening and embedded finance products that smaller processors cannot match.
The buying experience is the catch. Pricing is quoted, onboarding is sales-led, and small merchants can feel the enterprise machinery in the process. Worldpay does offer SMB-specific packages with quotes in minutes, which is better than pure enterprise competitors. But if you value published rates and self-serve signup, Stripe, Square or Helcim will feel like a different century.
What we like- Enormous scale at $2.3 trillion processed annually
- Dedicated offerings for SMBs, enterprises and software platforms
- Global acquiring with optimization tooling
Watch out for- Quote-based pricing with little transparency
- Sales-led process from first contact
- The SMB offering still carries enterprise-process DNA
How we chose
We built this list from the vendor's own pricing pages wherever rates are published: Stripe, Square, PayPal, Authorize.net and Helcim all disclose their numbers, and we used those rather than third-party roundups. For quote-only providers we evaluated positioning, scale, geographic coverage and feature depth from official homepages and documentation. We weighted total cost at realistic small-business volumes, payout speed, international support and the quality of self-serve onboarding. We excluded processors that do not serve US small businesses and pure merchant-account resellers with no direct product.
Reading the fine print on fees
Payment pricing has a vocabulary, and the quote only makes sense once you speak it. Flat-rate pricing charges one percentage plus a fixed fee on every transaction, simple to forecast and usually more expensive at volume. Interchange-plus passes through the card networks' wholesale cost and adds a fixed markup, cheaper at volume but variable month to month. Tiered or qualified pricing sorts transactions into buckets, which is where "rates as low as" marketing goes to mislead.
Beyond the headline rate, check five line items. Monthly or statement fees: $25 here and $10 there add up against a low-volume business. Cross-border fees: international cards and currency conversion commonly add 1 to 1.5 percent each. Chargeback fees: $15 to $25 per dispute is standard, win or lose. Payout timing: next-day versus two-day funding is a cash-flow decision, not a footnote. And the contract: early termination fees still exist in this industry, so confirm you can leave before you sign.
Match the model to your volume. Under a few thousand dollars a month, flat-rate simplicity from Stripe or Square usually wins. In the middle, Helcim's automatic interchange-plus or Authorize.net's gateway-only option cuts the effective rate without a negotiation. At real scale, Adyen, Checkout.com and Worldpay earn their sales process through authorization-rate optimization and global acquiring that flat-rate tools cannot touch.
Mistakes that cost small businesses real money
The most expensive mistake is choosing on brand alone. PayPal converts well, but running every transaction through its wallet rates when most customers would happily pay by card is a quiet margin leak. Price your actual mix: card-present versus online, domestic versus international, average ticket size. The cheapest provider for a $12 coffee shop ticket is rarely the cheapest for a $400 invoice.
The second mistake is ignoring foreign exchange. If even a fifth of your customers pay from abroad, cross-border and conversion markups can exceed your base processing cost. A provider with local acquiring in your customers' countries, or at least transparent FX fees, pays for itself quickly.
The third is never renegotiating. Processors price to your volume at signup and happily keep you there as you triple. Once you cross $5,000 to $10,000 a month, get competing quotes, including an interchange-plus option, and take the best number back to your current provider. The fourth is confusing the gateway with the merchant account: with Authorize.net's gateway-only option, for example, the two are separate bills and separate negotiations.
Frequently asked questions
What is the difference between a payment gateway, a processor and a merchant account?
The gateway is the technology that securely transmits payment data from your checkout. The processor moves the money between banks. The merchant account is the bank account that receives the funds. Modern providers like Stripe and Square bundle all three, which is simpler; Authorize.net lets you buy the gateway separately from the processing, which gives pricing flexibility.
How long until I actually receive my money?
Most providers pay out in one to two business days for US bank accounts. Stripe, Square and Helcim offer next-day or even instant options, sometimes for a small fee. New accounts often face longer holds during the first weeks while the provider verifies the business, so plan cash flow accordingly.
Can I switch payment providers later without rebuilding my checkout?
Yes, with preparation. The painful part is stored payment methods: cards saved for subscriptions live in the old provider's vault. Ask your new provider about card data migration before you switch; most, including Helcim, migrate it free. Also check contract termination fees with your current provider first.
What should I look for if I sell internationally?
Local acquiring in your customers' countries, support for local payment methods beyond cards, and transparent currency conversion fees. Adyen, Checkout.com and Worldpay lead here; Stripe covers the basics well. Compare the all-in cross-border cost, not just the domestic headline rate.
Do I still need to worry about PCI compliance?
Yes, but less than you think. Using hosted checkout pages, payment links or tokenized integrations from these providers keeps raw card data off your servers, which qualifies most small businesses for the simplest PCI self-assessment. Never store full card numbers yourself; let the provider's vault do it.
Why do providers hold or freeze funds?
Risk management. Sudden volume spikes, unusual transaction patterns or operating in a high-risk category can trigger reviews that pause payouts. It happens at every provider, including Stripe, Square and PayPal. Keep documentation ready, respond fast, and maintain a cash buffer so a review never becomes a crisis.
Sources we checked (12)
- https://stripe.com/pricing
- https://squareup.com/us/en/pricing
- https://www.paypal.com/us/business/pricing
- https://www.authorize.net/sign-up/pricing.html
- https://helcim.com/
- https://stripe.com
- https://squareup.com
- https://www.adyen.com
- https://braintreepayments.com/
- https://checkout.com/
- https://worldpay.com/
- https://www.airwallex.com/en-us/blog/top-payment-processors
Is your product missing or out of date?
We review this list regularly. Vendors can request a listing, send updated pricing or ask about featured placement.
Shihab Mia · Founder, Rankite
Shihab has spent more than a decade helping SaaS and e-commerce brands grow through search. He writes Rankite's software buying guides from pricing pages, documentation and public user reviews. More about Shihab.