Comparison · Updated September 15, 2026
Stax vs Square
Stax
B
Stax is a payments technology company founded in 2014 that partners with SaaS companies, ISOs, and SMBs to enable flexible, multi-channel payment processing and invoicing solutions, claiming a distinctive subscription-based pricing model with 0% interchange markup.
Square
A
Square offers simple, transparent payment processing ideal for small businesses. Flat-rate pricing, no monthly fees, and excellent software make it a top choice — but account holds and limited support are key concerns.
VS
Overview
Stax and Square sit at opposite ends of small-business pricing. Square charges nothing monthly and a flat 2.6% + 15¢ in person, and gives you free POS software, a $59 reader and an account you can close from the dashboard. Stax charges a subscription from $99 a month and then passes interchange through at cost plus 8¢ in person or 15¢ online, which is a far lower per-transaction cost but only pays for itself once volume is high enough to cover the subscription — Stax's own entry tier is sized for up to $150,000 a year. Square is graded A on Payment Review and Stax B. For most businesses under roughly that volume band, and for anyone who needs a point of sale, Square is the better choice; for an established business processing well above it, especially one invoicing or taking payments online, Stax's model saves real money.
Key Takeaways
- ✓Square's per-transaction cost is 2.6% + 15¢ in person on the free plan; Stax charges interchange at cost plus 8¢, with the markup replaced by a $99–$199+ monthly subscription.
- ✓Square has no monthly fee, no chargeback fee and no PCI fee; Stax publishes neither a chargeback nor a PCI fee on its rate card.
- ✓Square lets you cancel from the dashboard at any time; Stax is month-to-month with no cancellation fee, but merchants report a 30-day written notice requirement.
- ✓Square's free POS, $59 reader and instant transfers at 1.95% make it the complete small-business toolkit; Stax's included software is invoicing, recurring billing and a dashboard, with terminals from $125.
- ✓Stax rates 4.4 on Trustpilot to Square's 3.7, but Square holds the higher Payment Review grade (A against B) on the strength of pricing transparency, ease of use and contract terms.
Stax
Stax is for established businesses processing well above Stax's $150,000-a-year entry tier — professional services, field services, e-commerce and firms that invoice — where interchange-at-cost plus a fixed subscription beats a flat rate by a clear margin.
Square
Square is for new, small, seasonal and mobile businesses, and any retailer, restaurant or salon that wants free point-of-sale software, cheap hardware, no monthly fee and the freedom to leave at any time.
Overall Winner
🏆 Winner
Square
Aexpert grade
Runner-up
Stax
Why?
Square is the better choice for most of the businesses that search this comparison. It costs nothing until you sell, publishes every fee, charges no chargeback or PCI fee, includes a genuinely good free point of sale, and lets you leave from the dashboard — which is why it holds an A grade to Stax's B. Stax wins one thing decisively: the per-transaction cost, because interchange at cost plus 8¢ or 15¢ is far below any flat rate. That only becomes the deciding factor once your volume is large enough to absorb $99 to $199 a month and still come out ahead, a band Stax itself sizes at up to $150,000 a year for its entry tier and higher for the rest. Above that, and especially for businesses that invoice or take payments online rather than at a counter, Stax is the cheaper and more capable option and the honest recommendation.
Feature by feature
Detailed Comparison
Filter Options
Pricing model and rates
| Feature | Stax | Square |
|---|---|---|
| Pricing model | Monthly subscription + interchange at cost (0% markup) | Flat rate, no monthly fee on the free plan |
| Stax's subscription is set by annual processing volume: $99 a month up to $150,000, $139 for $150,000–$250,000, $199+ above that. Square's Plus plan is $49 a month per location and Premium $149, each with slightly lower in-person rates. | ||
| In-person (tap, dip, swipe) | Interchange + $0.08 Winner | 2.6% + 15¢ (Free); 2.5% + 15¢ (Plus); 2.4% + 15¢ (Premium) |
| Per transaction, before the subscription. Interchange on a US consumer card typically runs well under Square's flat rate, so the per-swipe saving is real; whether it covers $99 or more a month depends on volume. | ||
| Online and keyed | Interchange + $0.15 Winner | Online 3.3% + 30¢ (Free) or 2.9% + 30¢ (Plus, Premium, API); keyed 3.5% + 15¢ |
| Stax charges the same 15¢ for keyed and online. Square's keyed rate is its most expensive and the gap to Stax is widest here. | ||
| ACH bank payments | 1% capped at $10 | 1% on invoices, $1 minimum |
| Both price ACH at 1%; Stax caps it at $10 per transaction, Square sets a $1 minimum with caps that vary by plan. | ||
| International cards | Not disclosed | +1.5% on cards issued outside the US |
| Monthly fee | $99–$199+ by volume tier | $0 (Free); $49 per location (Plus); $149 per location (Premium) Winner |
Pricing model
Stax
Monthly subscription + interchange at cost (0% markup)
Square
Flat rate, no monthly fee on the free plan
Stax's subscription is set by annual processing volume: $99 a month up to $150,000, $139 for $150,000–$250,000, $199+ above that. Square's Plus plan is $49 a month per location and Premium $149, each with slightly lower in-person rates.
In-person (tap, dip, swipe)
Stax
Interchange + $0.08
Winner
Square
2.6% + 15¢ (Free); 2.5% + 15¢ (Plus); 2.4% + 15¢ (Premium)
Per transaction, before the subscription. Interchange on a US consumer card typically runs well under Square's flat rate, so the per-swipe saving is real; whether it covers $99 or more a month depends on volume.
Online and keyed
Stax
Interchange + $0.15
Winner
Square
Online 3.3% + 30¢ (Free) or 2.9% + 30¢ (Plus, Premium, API); keyed 3.5% + 15¢
Stax charges the same 15¢ for keyed and online. Square's keyed rate is its most expensive and the gap to Stax is widest here.
ACH bank payments
Stax
1% capped at $10
Square
1% on invoices, $1 minimum
Both price ACH at 1%; Stax caps it at $10 per transaction, Square sets a $1 minimum with caps that vary by plan.
International cards
Stax
Not disclosed
Square
+1.5% on cards issued outside the US
Monthly fee
Stax
$99–$199+ by volume tier
Square
$0 (Free); $49 per location (Plus); $149 per location (Premium)
Winner
Best For Your Business
Recommendations based on your business type
New retail shop, café or salon
Recommended
Square
Square's free POS, $59 reader and no monthly fee cover everything a counter business needs on day one, and there is no subscription to justify while volume is still building.
Professional services firm invoicing $20,000+ a month
Recommended
Stax
At that volume the interchange-at-cost saving on keyed and online payments clears the $99–$139 subscription with room to spare, and invoicing, recurring billing and account updater are included.
Restaurant
Recommended
Square
Stax does not sell a restaurant point of sale; Square's restaurant edition, Handheld and Register are built for it.
Established e-commerce store processing $30,000+ a month
Recommended
Stax
Square's online rate is 2.9–3.3% + 30¢; Stax charges interchange plus 15¢, so the monthly saving on that volume is well above the subscription, and the Stax API and hosted payment pages are included.
Seasonal, mobile or pop-up seller
Recommended
Square
A fixed $99 a month is dead money in the off-season; Square charges only when you sell and you can pause without cancelling anything.
High-risk business (gambling, firearms, collections)
Neither. Stax's review lists high-risk industries as unsupported and Square's lists high-risk businesses among those it is not recommended for. Look at a high-risk specialist instead.
Stax: Best for 2 use cases
Square: Best for 3 use cases
Frequently Asked Questions
Common questions about this comparison
Per transaction, yes: Stax passes interchange through at cost and adds 8¢ in person or 15¢ online, while Square charges 2.6% + 15¢ in person and 2.9–3.3% + 30¢ online. In total, only once your volume is high enough for that saving to exceed Stax's $99 to $199+ monthly subscription. Stax sizes its $99 tier for up to $150,000 a year, which is a fair guide to where the model starts to make sense.
Not on the free plan. Square Plus is $49 a month per location and Premium $149 a month per location, and each lowers the in-person rate by a tenth of a point and the online rate to 2.9% + 30¢. Hardware is bought separately, from a $59 contactless and chip reader.
Stax's subscription is set by annual processing volume: $99 a month for up to $150,000, $139 for $150,000 to $250,000, and $199 or more above that, with custom quotes for larger merchants. On top of that you pay interchange at cost plus 8¢ per in-person transaction or 15¢ per keyed or online transaction, and 1% capped at $10 for ACH.
Stax, on cost. A flat rate gets expensive at volume — Square's own review says so — while a subscription is fixed, so the more you process the smaller Stax's effective rate becomes. Square offers custom pricing to merchants over $250,000 a year, so a high-volume business that wants Square's software should ask for a quote before deciding.
Neither has a long-term contract or an early-termination fee. Square accounts can be closed from the dashboard at any time. Stax is month-to-month and its pricing page states there are no cancellation fees, but its review and merchant reviews report that cancelling requires 30 days' written notice and signed closure paperwork.
Stax resells terminals rather than building its own: the SwipeSimple B350 mobile reader at $125, the Dejavoo QD4 countertop terminal at $310, the QD2 wireless terminal at $495 and a D1 cloud register, with an optional $19-a-month protection plan. Square builds its own line, from the $59 reader to the $899 Register.
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