Best Payment Gateways for Ecommerce: 2026 Comparison

TL;DR

For ecommerce merchants between $10K and $1M monthly volume, the cheapest published options are interchange-plus and subscription pricing, not flat rates. Helcim wins on price below about $50K a month: interchange-plus 0.50% + $0.25 online with no monthly fee and automatic volume tiers. Stax takes over from $50K a month, when its subscription ($199 a month above $250K a year) costs less than a percentage markup. Stripe wins for developer-heavy or global stacks. Square fits small omnichannel sellers, and PayPal works best as a second checkout button. Worldpay and Clover are situational. The at-a-glance table below breaks it down.

How we ranked

We scored each gateway against five operator-relevant criteria using each processor's public pricing page and the published interchange schedules from Visa and Mastercard. Provider prices were checked in Oct 2026.

• Effective rate at $50K and $250K monthly volume. From our effective-rate dataset, which assumes a $50 average sale, a mix of 60% credit and 40% debit, and an online interchange estimate of 1.70%.
• Pricing model. Flat-rate, interchange-plus, or subscription. Each becomes optimal at a different volume tier.
• Contract and ETF. Month-to-month versus multi-year lock-ins with early termination fees.
• Settlement speed. Standard 1 to 3 business days versus instant deposit add-ons at 1.5 to 1.95% per transfer.
• Online feature set and lock-in. 3DS, hosted fields, network tokens, level 2/3 data for B2B, plus whether hardware is locked to a single processor.

At a glance

Stripe

Stripe charges 2.9% + $0.30 on standard online transactions, per its public pricing page. There is no monthly fee, no setup fee, and no contract. In our dataset at $250K monthly volume, that flat rate works out to 3.50% ($8,750), against 2.45% ($6,125) for Helcim's interchange-plus online rate.

Stripe's value is the developer surface: hosted Checkout, Elements, Payment Intents API, Connect for marketplaces, and Radar for fraud. Standard payouts arrive in 2 business days; Instant Payouts cost 1.5% (minimum 50 cents).

Where it wins: developer-led teams, marketplaces, and international merchants who need to accept 135+ currencies and local payment methods without re-platforming.

Where it loses: U.S. merchants who do not need the API depth. The flat rate compounds. In our dataset a $50K monthly merchant pays $1,750 a month on Stripe against $1,275 on Helcim's interchange-plus schedule, $475 more.

Square

Square's online rate is 2.9% + $0.30 on its paid plans or through the Online API, matching Stripe's flat rate; on the free plan it is 3.3% + $0.30. Keyed transactions are 3.5% + $0.15. The free plan has no monthly fee; Plus costs $49 and Premium $149 a month per location, per the Square pricing page.

Square works when the same merchant takes payments in person and online. The card reader hardware, the POS, and the online store share inventory and customer data without integration work. Funding is next business day at no charge; instant or same-day transfers cost 1.95%.

Where it wins: omnichannel small businesses under $50K monthly, single-location retail, food service, and pop-ups that need a working checkout quickly.

Where it loses: pure ecommerce merchants over $40K monthly, where interchange-plus and subscription pricing cost less. Like any aggregator, Square can hold funds when activity changes sharply, so ask how reserves work if your ticket size or volume swings.

Helcim

Helcim runs interchange-plus 0.50% + $0.25 online with no monthly fee, no setup fee, and no contract. Volume above $50K, $100K, $500K and $1M monthly triggers automatic margin reductions that Helcim publishes on its pricing page.

Helcim's gateway includes hosted payment pages, a virtual terminal, automatic Level 2/3 interchange optimization (Helcim keeps 30% of the savings it produces), ACH at 0.5% + $0.25 capped at $6 (plus 0.05% on amounts over $25,000), and recurring billing at an extra 0.4% per recurring transaction. Deposits arrive the next business morning at no charge.

Where it wins: U.S. and Canadian ecommerce merchants up to about $50K monthly volume who want transparent pricing without sales calls, and larger merchants who want no monthly fee.

Where it loses: merchants who need instant payouts, which Helcim does not offer, or same-country acquiring outside North America. From $50K a month, Stax costs less in our dataset.

Stax

Stax charges a monthly subscription of $99 to $199 or more, set by annual volume, plus interchange and $0.15 per online transaction, per its pricing page. There is no percentage markup. At $50K monthly volume, or $600,000 a year, the $199 tier applies; with our 1.70% online interchange estimate and a $50 average sale, that lands near 2.40% effective, against 2.55% for Helcim at the same volume.

The break-even versus Helcim falls between $10K and $50K a month in our dataset: at $10K Helcim is cheaper (2.70% against 2.99%), and at $50K Stax is. At $250K monthly, Stax costs $5,200 against $6,125 for Helcim, a saving of $925 a month, and the gap stays in Stax's favor at $1M (2.02% against 2.15%).

Stax includes a payment dashboard and ACH at 1% capped at $10. Hardware is sold separately. The pricing page lists no cancellation fees but does not publish a contract length.

Where it wins: established ecommerce merchants from $50K monthly with predictable card mixes.

Where it loses: merchants around $10K monthly, where the subscription outweighs the markup it removes. The fixed per-transaction fee also weighs more on small tickets.

Payment Depot

Payment Depot sells interchange-plus pricing by quote. Its pricing page (archived Oct 2025) lists no monthly or per-transaction price, only $0 setup and no cancellation fees, so the full cost cannot be worked out from public information.

Whether it beats Stax or Helcim depends on the markup and any monthly fee you are quoted and on your transaction count, so get the full schedule in writing and compare it with their published costs.

Ask for setup time, funding time, and support hours in writing, since none are on its pricing page.

Where it wins: merchants who want interchange-plus pricing and will get a full written quote.

Where it loses: small-ticket high-frequency businesses (subscriptions under $25, digital goods, micro-SaaS). If the quote carries a per-transaction fee, it compounds, and a 2.9% flat rate may still come out cheaper.

Clover

Clover sells POS hardware and software tied to its payment processing. On Clover.com the software plans run from $0 on Starter to $29.95 on Essentials and $84.95 and up on Retail Growth. In-person rates run from 2.6% + $0.10 on Starter down to 2.3% + $0.10 on the Growth bundles, and keyed or online cards cost 3.5% + $0.10 on every bundle, per Clover's pricing page. Hardware subscriptions run 36 months and cannot be canceled, and Clover sold through a bank can carry different rates and terms.

Clover's online checkout is a basic hosted page or plugin. Reporting is strong on in-person sales and weaker on ecommerce attribution. Standard deposits take 1 to 3 days; Rapid Deposit costs 1.75%.

Where it wins: small retail and restaurant operators who want a turnkey hardware-plus-software bundle and accept payments mostly in person.

Where it loses: pure ecommerce. A 3.5% + $0.10 keyed rate (3.70% on a $50 sale) makes Clover one of the most expensive options in this comparison for online-only merchants; only PayPal Checkout costs more.

PayPal

PayPal's PayPal Checkout rate is 3.49% + $0.49, and its Advanced Credit and Debit card processing is 2.89% + $0.29 (subject to PayPal's approval), per the PayPal business fee schedule. The $0.49 per-transaction fee is the highest in this comparison and disproportionately hurts small-ticket merchants.

PayPal still adds value at the checkout layer: many shoppers already have a PayPal account and trust the wallet. Test whether the button lifts your own conversion. Many merchants run PayPal as a secondary option alongside Stripe or Helcim, not the primary processor.

Standard withdrawals to a bank are free and instant transfers cost 1.5% (minimum 50 cents). PayPal can hold payments for new or higher-risk sellers, so ask about holds before launch.

Where it wins: merchants who need PayPal-as-a-button next to a primary card gateway.

Where it loses: as a primary processor over $25K monthly. The flat-rate plus 49-cent per-transaction fee compounds badly on average tickets under $50.

Worldpay

Worldpay prices custom: the margin, contract length and termination terms are negotiated per merchant. There is no public flat-rate on the Worldpay site. Worldpay has been part of Global Payments since January 2026.

Large merchants with negotiating room may get pricing below published interchange-plus offers, but Worldpay publishes no rates, so there is nothing to compare until you have a written quote. Smaller merchants usually do better with a published price list like Helcim's or Stax's.

Ask for setup time, contract length, auto-renewal terms and any early termination fee in writing.

Where it wins: large merchants that can negotiate and want one enterprise contract.

Where it loses: SMB and mid-market merchants. A sales process and unpublished pricing make it the wrong fit.

Verdict

For U.S. ecommerce merchants up to about $50K monthly volume, Helcim is the cleanest answer: interchange-plus 0.50% + $0.25, no monthly fee, no contract, automatic tiered discounts as you grow. Against Stripe at $250K monthly volume in our dataset, Helcim saves $31,500 a year.

Stripe wins when the team is developer-heavy, the product is a marketplace or global SaaS, or the API depth justifies paying 3.50% against 2.45% for Helcim at $250K a month in our dataset.

Stax wins from $50K monthly with a stable card mix. In our dataset it is the cheapest option here at $50K, $250K and $1M a month online. Payment Depot sells interchange-plus by quote only, so get a written quote and compare it with Stax's published cost.

Square wins for true omnichannel under $50K monthly. PayPal stays as a secondary button. Clover stays in-store-first. Worldpay only makes sense for large merchants with room to negotiate.