Finix vs. Stax: How they compare
Stax's subscription model can work well for established SMBs. For businesses that need card data portability, platform payments, or a direct processor relationship, Finix offers greater ownership and flexibility.
Finix and Stax pricing compared
Finix | Stax | |
|---|---|---|
Pricing model | Subscription from $250/mo + interchange-plus per transaction | Subscription-based: flat monthly fee + interchange at cost with 0% percentage markup + small cents per transaction. Up to $150K/yr: $99/mo; $150K–$250K/yr: $139/mo; $250K+/yr: $199+/mo |
In-person | 0% markup on interchange + $0.15/transaction (Amex: 0.30% + $0.15) | Interchange + $0.08/transaction (0% percentage markup) |
Online payments | Interchange + 0% + $0.15/transaction (Amex: 0.30% + $0.15) | Interchange + $0.15/transaction (0% percentage markup) |
Interchange optimization | Full Level 2 & 3 support | L2/L3 support available — Stax passes interchange at cost, so L2/L3 savings flow directly to the merchant |
Virtual terminal | Included | Included |
Payment links | Included | Included |
ACH transactions | 1.00% (max $10.00) + $0.25 | 1% per transaction, capped at $10 |
ACH validation | $0.55 flat | Included via account verification |
Instant payouts | 1.50% | Next-day funding standard; expedited funding available for an additional fee |
Fraud detection | Included (machine learning) | Included |
Support fees | Included — dedicated account manager | Dedicated account manager included |
Technology fees | None | None beyond subscription |
Best fit volume | All merchant volumes | Best value for merchants processing $5K+/month; lower volumes may not offset subscription cost |
Card data portability | Full portability — merchants own and can migrate card data | Card data held by Stax gateway; portability on migration |
Quick recap of Direct Merchant Pricing Comparison
Stax’s pricing model differs from many processors by charging a monthly subscription plus a flat per-transaction fee above interchange, rather than a percentage markup. Finix also passes through interchange with no percentage markup on standard Visa, Mastercard, and Discover transactions, charging a $250 monthly membership fee plus $0.15 per transaction. The main difference is how the two providers structure their monthly fees and per-transaction costs.
Platform and marketplace features compared
Finix | Stax | |
|---|---|---|
Platform product | Finix platform payments — purpose-built | Stax Connect — embedded payments for SaaS companies and ISVs; separate product from Stax Pay |
Pricing models | Flat-rate or dynamic, fully configurable per merchant | Custom pricing per partner; Stax Connect pricing is not publicly listed |
Interchange fee optimization | Full Level 2 & 3 support | Interchange at cost passed through; L2/L3 optimization available |
Merchant payout | $0.50 per next-day ACH payout; $0.75 per same-day ACH payout | Custom pricing; payout fees not publicly disclosed |
White-labeling | No additional cost | Supported — white-label capabilities included in Stax Connect |
Sub-merchant onboarding | Supported — direct API | Supported — Stax manages enrollment, compliance, and underwriting on behalf of partner |
PayFac / revenue share model | Supported | Supported — referral, reseller, and PayFac-as-a-Service models available |
ACH transaction cost | 1.00% (max $10.00) + $0.25 | Custom pricing; ACH fees not publicly disclosed |
Instant payouts to sub-merchants | 1.50% | Available; pricing not publicly disclosed |
Machine learning and fraud detection | Included | Included |
Support model | Dedicated account manager included | Full-service partnership team — Stax manages pre-sales, onboarding, and tier-1 support for ISV partners |
Time to launch | Direct integration | Stax claims payments ecosystem buildout in as little as 30 days |
Pricing as of June 2026. Stax subscription tiers: up to $150K/yr: $99/mo; $150K–$250K/yr: $139/mo; $250K+/yr: $199+/mo. Applies to U.S.-based businesses. Stax Connect pricing is custom and not publicly listed — verify with Stax directly before publication.
Quick recap of Platform & Marketplace Pricing Comparison
Stax Connect gives software platforms a managed approach to embedded payments, with a single API and support for merchant onboarding, risk management, compliance, and payment operations. Finix gives platforms direct control over the payment experience, with configurable merchant pricing, white-label capabilities, sub-merchant onboarding, and support for migrating payment data from another provider.
What growing businesses should know
Finix
Certified direct processor connecting to Visa, Mastercard, Discover, and Amex. Each merchant receives a dedicated merchant account.
Full card data portability. Merchants own their tokenized card data and can migrate it without requiring customers to re-enter payment details
Transparent interchange-plus pricing with 0% percentage markup on Visa, Mastercard, and Discover, plus a $0.15 per-transaction fee.
Accepts payments online, in-person, and across channels from a single platform
Platform and marketplace payments built into the core product. No separate products requiring a separate contract
Dedicated account manager included for all merchants from day one
Stax
Subscription-based pricing with 0% percentage markup on interchange. Merchants pay actual interchange cost plus flat cents per transaction ($0.08 in-person, $0.15 online), making it cost-effective for high-volume or high-ticket businesses
Over 30,000 businesses trust Stax, processing more than $30 billion in payments
Stax Connect serves SaaS and ISV platforms with embedded payments, white-labeling, and PayFac-as-a-Service, managed by Stax's full-service partnership team
CardX by Stax provides compliant credit card surcharging automation, reducing or eliminating net processing costs for eligible businesses
Next-day funding standard; instant and same-day options available as add-ons
ACH processing, recurring billing (Stax Bill), and invoicing included in the platform
Integration and customization options
Finix
RESTful API with webhooks and real-time event streams covering card payments and bank transfers
No-code onboarding tools alongside full API access. Non-technical teams can get started without dedicated dev resources
Tokenization and hosted fields to reduce PCI scope, with full card data portability on migration
Dedicated sandbox environment for integration testing
White-labeled checkout pages, payment links, and virtual terminal included, no extra development required
Stax
RESTful API supports custom integrations with CRM, accounting, and business software (QuickBooks, HubSpot, Zapier, WooCommerce, Google Workspace)
Android and iOS SDKs for mobile payment acceptance
Stax Connect single API integration for ISVs — pre-built enrollment, automated settlements, and risk management; Stax claims a 30-day launch timeline
iFrame support and webhook integration for embedded checkout flows
Stax Bill API supports recurring billing, subscription lifecycle management, and dunning (failed payment recovery)
Frequently asked questions
Both Finix and Stax use interchange-based pricing with no percentage markup on standard card transactions. Stax charges $0.08 per in-person transaction and $0.15 per online transaction, alongside a monthly subscription starting at $99. Finix charges $0.15 per transaction for Visa, Mastercard, and Discover, alongside a $250 monthly membership fee. Amex transactions with Finix include an additional 0.30% fee. The overall cost of either option depends on your processing volume, transaction mix, and payment methods.
Both models pass through interchange without adding a percentage markup on standard Visa, Mastercard, and Discover transactions. The main differences are the monthly and per-transaction fees. Stax charges $0.08 for in-person transactions and $0.15 for online transactions, while Finix charges $0.15 per transaction for standard cards. Stax's subscription starts at $99 per month, while Finix charges a $250 monthly membership fee. Which costs less depends on how and how much your business processes.
Yes, through Stax Connect, a separate embedded payments product for SaaS companies and ISVs. Stax Connect offers white-labeling, a single API integration, sub-merchant onboarding, and a full-service partnership team that manages compliance, enrollment, and tier-1 merchant support. The Stax Connect Plus model means ISVs can offload much of the operational work to Stax. The key difference from Finix is the underlying processor relationship: Stax Connect operates on a PayFac or reseller model where Stax retains the direct connection to the card networks. Finix is a certified direct processor, giving platform partners a more direct relationship and full card data portability.
This is an important question to ask before signing with any processor. Finix provides full card data portability and tokenized card data can be migrated to another processor without requiring customers to re-enter their payment details. Stax's approach to card data portability on migration should be confirmed directly with Stax before signing, as it depends on the gateway and tokenization configuration in use. This matters especially for businesses with large numbers of stored customer payment methods or subscription billing.
Stax is a strong fit for established SMBs processing $5,000 or more per month with consistent volume and higher average ticket sizes and the subscription model pays off quickly in those conditions. Stax Connect is a compelling option for SaaS companies and ISVs that want to embed payments quickly and prefer a managed model where Stax handles operational complexity. Finix is a better fit for businesses that need direct processor control, full card data ownership, platform and marketplace payment capability built into the core product, or flexibility across a wider range of volume levels without a subscription floor.
Yes. Finix supports full card data portability and tokenized card data can be migrated without requiring customers to re-enter payment details. The migration process depends partly on how your card data is currently stored in Stax's gateway; Finix's team will work through the specifics with you. Talk to our team to understand the steps and timeline for your setup.
Need help choosing the next payment solution?
Chat to our team. We'll help you find the right fit.
Whether you're weighing Stax's subscription model against Finix's interchange-plus pricing, evaluating platform payment options, or thinking about card data portability, our team can walk you through the comparison for your specific transaction profile.