Finix vs. Stax: How they compare

Both Finix and Stax use interchange-based pricing and merchants pay the actual interchange cost rather than a flat blended rate. The structural difference is how the processor's fee is applied. Stax charges a flat cents-per-transaction fee above interchange ($0.08 in-person, $0.15 online) with no percentage markup, plus a monthly subscription starting at $99. Finix uses a traditional interchange-plus model with a small percentage markup per transaction and a subscription from $99. For merchants with high average ticket sizes, Stax's flat cents model can produce lower per-transaction costs. For merchants with lower average tickets or lower overall volumes who want to avoid a monthly subscription floor, Finix's model may be more predictable.

It depends on your transaction profile. Stax charges interchange at cost plus flat cents per transaction with no percentage markup on top. On a $500 transaction, Stax's $0.08 fee is meaningfully less than a 0.15% markup ($0.75). On a $10 transaction, the difference is negligible. The subscription cost ($99–$199+/month) means low-volume merchants subsidize the pricing model regardless of transaction count. Merchants with consistent volumes and high average tickets typically benefit most from Stax's structure. Finix's interchange-plus model works well across a broader range of volume levels without a subscription requirement at entry.

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.