CardX Review (2026): Credit Card Surcharging Pricing, Features, Pros & Cons
Last update at April 28, 2026
CardX by Stax is a credit card processing solution built around a single concept: merchants pay nothing on credit card transactions, and customers pay a 3.5% surcharge instead. For businesses frustrated by processing fees, CardX offers zero net cost on credit card sales. But surcharging comes with legal complexity, customer perception risks, and real limitations that this CardX review addresses directly.
Key Features
Summary
| Feature | Details |
|---|---|
| Full Name | CardX by Stax |
| Best For | Businesses wanting to pass credit card processing costs to customers |
| Core Model | Merchant pays 0% on credit cards; customer pays 3.5% surcharge |
| Monthly Fee | Approx. $29-$35/month |
| Debit Card Fee | Standard debit interchange rate; no surcharge applied to debit |
| State Availability | 48 states + Washington DC (NOT Connecticut or Massachusetts) |
| Contract | No long-term contract; cancel anytime |
| Hardware | SwipeSimple terminal; no full POS system included |
| Notable Credential | Mastercard's exclusive surcharging partner |
| Parent Company | Stax (acquired CardX in 2021) |
| Founded | 2013 (Chicago, IL) |
NOTE: 78% of consumers consider surcharging unfair (CardX’s own data). Surcharging is a strategic decision, not just a financial one. Evaluate customer acceptance risk before recommending.
CardX Key Features
Automated Compliance
CardX’s primary differentiator. The system automatically detects card type (credit vs. debit), applies the surcharge only to credit cards, generates compliant point-of-sale signage, posts disclosures before transaction completion, and handles card network registration. This eliminates the main reason businesses shy away from surcharging: manual compliance risk and potential card brand penalties.
In-Person Payments
SwipeSimple-compatible smart terminal accepts EMV chip, NFC contactless, and magnetic stripe. Automatically shows customers the surcharge amount before transaction approval. No full POS system included; businesses needing inventory, scheduling, or advanced reporting must use third-party POS via Stax API (may carry additional fees).
Online Payments
Payment gateway, API integration, hosted payment pages, and payment links. 3.5% surcharge applied automatically to online credit card transactions; displayed before customer confirms. Compatible with Shopify and WooCommerce. Developer API builds custom payment solutions on CardX’s surcharging infrastructure.
Virtual Terminal
Included at no extra charge. Merchants key in card-not-present transactions from any browser; surcharging logic applies automatically. Suitable for phone orders and direct client billing.
Debit Card Auto-Detection
Automatically identifies debit cards; applies no surcharge and informs customer. Merchant pays standard debit interchange. This automation is critical: manually applying surcharges to debit cards violates federal Regulation II and Visa/Mastercard rules, with significant penalty exposure.
Reporting and Reconciliation
Daily settlement reports, surcharge amounts collected, and transaction breakdowns. Reconciliation tools help manage the distinction between gross sales (including customer-paid surcharges) and net merchant proceeds.
CardX Pros and Cons
| Pros | Cons |
|---|---|
| 0% processing cost on credit cards for the merchant | 78% of consumers consider surcharging unfair (CardX's own data) |
| Mastercard's exclusive surcharging partner | Not available in Connecticut or Massachusetts |
| Automated compliance: detection, disclosures, network registration | No full POS system; limited hardware ecosystem |
| No long-term contract; cancel anytime | Merchant still pays normal rates on debit card transactions |
| 48 states + DC; broad availability | Not suitable for high-risk businesses |
| Online, in-person, and virtual terminal all supported | Some third-party POS integrations require additional fees |
| Backed by Stax infrastructure and payment technology | May deter customers who prefer credit card payments |
| Auto-detection prevents illegal debit surcharging | Exact pricing requires contact; not fully self-serve |
Pricing
CardX Pricing (2026)
| Fee | Amount | Notes |
|---|---|---|
| Monthly base fee | Approx. $29-$35/month | Contact CardX for exact current rates |
| Credit card surcharge | 3.5% (paid by customer) | Merchant receives 0% net cost on credit card sales |
| Debit card processing | Standard interchange (paid by merchant) | No surcharge; merchant bears normal cost |
| Hardware | Varies by terminal | SwipeSimple terminal; pricing by inquiry |
| Contract | None | Month-to-month; cancel anytime |
| Setup fee | Not stated | Confirm at sign-up |
Real-cost example: $30,000/month in credit card sales: merchant pays $0 (customers pay 3.5% surcharge). Only cost = $29-$35/month. Compare to 2.6%-3.0% standard fees on same volume = $780-$900/month. Potential monthly savings: $750+ for qualifying businesses.
NOTE: Visa caps surcharges at 3% (as of April 2023). CardX applies 3.5%, which is within Mastercard’s cap. Verify Visa compliance for your specific processing before launch.
Things To Note
CardX vs Competitors
| Feature | CardX by Stax | Square | Helcim | Payment Depot |
|---|---|---|---|---|
| Model | Surcharging (0% to merchant) | Flat-rate (no surcharging) | Interchange-plus | Interchange-plus |
| Merchant Cost | $0 on credit | 2.6%+$0.10/swipe | Interchange + margin | Interchange+$0.15 |
| Customer Cost | 3.5% surcharge on credit | None (merchant absorbs) | None | None |
| Monthly Fee | Approx. $29-$35 | $0 | $0 | $79 |
| Full POS | No | Yes | No | No |
| State Limit | Not CT or MA | None | None | US only |
| Best For | Service/B2B/Government | Low-volume retail | Low-mid volume | High-volume SMBs |
In A Nutshell
What Is CardX?
CardX is a compliant credit card surcharging platform founded in 2013 by Jonathan Razi in Chicago, Illinois. Acquired by Stax in 2021 (now CardX by Stax), it automates surcharging compliance: card type detection, applying surcharges only to credit (never debit), card network registration, compliant disclosures and signage, and fee caps per Visa and Mastercard rules.
CardX is Mastercard’s exclusive surcharging partner. The company filed a brief in Expressions Hair Design v. Schneiderman, the 2017 US Supreme Court case that confirmed businesses have a First Amendment right to disclose and charge credit card fees. This case established the legal foundation for modern surcharging programs in the US.
How CardX Works
Credit card payment: customer pays sale price + 3.5% surcharge. Merchant receives full sale price with 0% processing fee deducted. Debit card payment: no surcharge applied; merchant pays standard debit interchange rate. Cash: no surcharge. For government agencies and educational institutions, CardX allows surcharging on both credit and debit with variable rates based on card type.
KEY CAVEAT: CardX’s own data shows 78% of consumers consider surcharging unfair. This does not mean surcharging will harm your business, but customer communication and clear signage are essential to maintaining customer relationships.
Who Is CardX Best For?
Best fit: service-based businesses (plumbers, landscapers, contractors, HVAC, auto repair), convenience stores, medical and dental practices, legal and professional services firms, and government or educational institutions. These businesses have captive or invoice-paying customer bases where surcharging is accepted or legally mandated.
Poor fit: competitive consumer-facing retail and restaurant environments where customers have easy alternatives and will take business elsewhere to avoid a surcharge. Also not available in Connecticut or Massachusetts, and not approved for high-risk merchant categories.
Is Surcharging Right for Your Business?
Four questions to answer before choosing CardX: (1) Will your customers accept a surcharge? (2) What percentage of transactions are credit vs. debit? If 70% are debit, savings only apply to the 30% credit volume. (3) Is surcharging fully legal in your state? (4) Can you deliver clear customer communication to avoid chargebacks and complaints?
Is CardX Worth It? Our Verdict
CardX delivers exactly what it promises: compliant, automated surcharging that enables merchants to accept credit cards at zero net processing cost. Backed by Stax’s infrastructure and Mastercard’s exclusive partnership designation, it is the most credible surcharging solution in the US market in 2026.
The honest caveat: surcharging is a customer relationship decision as much as a financial one. Professional services, medical practices, contractors, and B2B businesses typically benefit most. Consumer-facing competitive retail and restaurants must model customer attrition risk carefully before switching.
Best for: Service businesses, B2B merchants, professional services, government and educational institutions in the 48 available states where eliminating credit card fees outweighs the customer friction of a 3.5% surcharge at checkout.
Not for: Merchants in Connecticut or Massachusetts, high-risk businesses, consumer-facing competitive retail and restaurant environments, or businesses where debit cards dominate and surcharge savings would be minimal.
FAQs About CardX
What is CardX?
CardX (now CardX by Stax) is a compliant credit card surcharging solution that allows businesses to accept credit cards at 0% net cost by passing a 3.5% surcharge to the customer. Founded in 2013, acquired by Stax in 2021, it is Mastercard’s exclusive surcharging partner. Available in 48 US states and Washington DC.
How does CardX work?
When a customer pays by credit card, CardX applies a 3.5% surcharge. The merchant receives the full sale price with no processing fee. When a customer pays by debit, no surcharge applies; the merchant pays standard debit interchange. CardX automatically detects card type, posts required disclosures, and registers merchants with card networks.
What does CardX cost?
Approx. $29-$35/month (contact CardX for current pricing). Merchants pay 0% on credit card transactions; customers pay the 3.5% surcharge. Merchants pay standard interchange on debit transactions. No long-term contract.
Is CardX available in all states?
CardX is available in 48 states and Washington DC. It is NOT available in Connecticut or Massachusetts. Confirm your specific state’s rules with CardX before signing up.
Who owns CardX?
CardX was founded by Jonathan Razi in 2013 and acquired by Stax (formerly Fattmerchant) in 2021. It operates as CardX by Stax, with Stax’s headquarters in Orlando, Florida.
How does CardX compare to traditional credit card processing?
Traditional processors charge merchants 2.5%-3.5% per credit card transaction. CardX eliminates this cost for the merchant by passing it to the customer as a surcharge. The trade-off is customer perception: 78% of consumers consider surcharging unfair per CardX’s own data. Businesses must evaluate whether savings outweigh potential customer friction before switching.
