If you’re reading this article, you might have tried Sola Payments (formerly known as Cardknox) and want to switch, or you’re looking for a similar solution that better fits your business needs.

You might be facing the following challenges:

• Limited control: You’re tired of being told what pricing to set, and you don’t have full control over your onboarding, reporting, or checkout experience.
• Slow support: It takes a long time to get help: you need to submit a ticket, and while you’re waiting, your merchants are losing money and getting angry at you.

To help you find the right solution for your SaaS, this article will compare the top 5 Cardknox competitors.

In this article:

• Comparison table: 5 alternatives to Cardknox
• Fiska
• Rainforest
• Tilled
• Finix
• Stax

Need an embedded payments provider that helps you take control of your payments? Book a call with our payments experts.

Comparison table: 5 alternatives to Sola Payments

*All information presented in this blog has been sourced from provider websites and is accurate to the best of our knowledge at the time of writing (June 2026). However, providers may update their offerings, and details can change over time.

Fiska

There are lots of embedded payment solutions that target SaaS platforms. Since we’re writing this guide, we’ll start by telling about ourselves.

Fiska was specifically built for SaaS platforms. We act as a true partner by giving you full control over how payments are managed and delivered.

Here’s what you get when you partner with Fiska:

A true payments partner with aligned interests

We operate on a true revenue share business model, meaning our incentives are fully aligned with your success. In other words: if you don’t get paid, neither do we.

We do this in the spirit of partnership, and it’s the reason we don’t charge any monthly platform fees. Our earnings are directly tied to the earnings of our SaaS customers, and because we don’t make guaranteed revenue, we’re motivated to help you grow long after onboarding.

We do this by acting as your fractional Head of Payments; we’ll provide you with all the information, tools, and support you need to make the right decisions for your business. Our team even offers strategic advice to help you optimize your payments, though we’ll never dictate how you should serve your customers.

Read more: Why Fiska doesn’t charge fees (and how our partnership model works)

Complete control over your payment experience

We believe that SaaS businesses should have full control over their payments experience.

Here’s how we return control to our SaaS customers:

• White-labeling: Everything happens under your name, including customized onboarding, checkout services, point-of-sale (POS) terminals, receipts, and support.
• Embedded onboarding: Our merchant onboarding application can be fully embedded into your platform, and it’ll never take merchants to a third-party site.
• Control over pricing: We offer fixed rate, interchange-plus, and blended options. Pricing models are yours to design, and you’re able to set different pricing for different clients.

You have the final say over all of this, but as your payment partner, we can offer strategic advice every step of the way. Our goal is to become an extension of your team so that you don’t have to worry about managing payments.

Wondering which pricing model is best for your business? Read more here : What you need to know about pricing models in payments

Intentionally simple technology

Fiska is designed to be as easy to integrate as possible. Even if you don’t have a seasoned payments expert in-house, you can embed payments quickly thanks to our helpful team and comprehensive documentation.

Our payments technology is simple and effective for SaaS, and our features include:

• One omnichannel API: Fiska manages everything payments-related, including compliance, risk management, certifications, tokenizing payment data, and data security. We offer omnichannel payments, so you can accept both online payments, mobile payments, and in-store payments through the same API.
• Universal tokenization: When you use Fiska’s universal tokenization, your merchants’ customers only need to enter their card details once. From then on, those credentials can be used seamlessly across web, mobile, or in-person payments (through your connected POS system), without re-entering card info or triggering unnecessary security challenges.Think of how Uber works: you add your card once, and whether you order a ride, a food delivery, or rent a bike, it just works. Or how Amazon lets you pay across devices without any hassle. That’s because they’ve built an advanced payments infrastructure to store and reuse card credentials securely.With Fiska, SaaS platforms can offer that same level of payment fluidity to their merchants, without needing an internal payments team or custom vaulting solution. These kinds of features used to require a massive payments team and custom infrastructure. Fiska gives SaaS platforms that power out of the box, making it effortless for your merchants to accept payments.
• New feature implementation: We’re always updating our infrastructure to support the latest in payment innovation. Our streamlined SDKs are built for speed and simplicity, letting your team implement new features like tokenization, embedded onboarding, or payout logic with just a few lines of code.Whether you’re integrating a new pricing model or launching a mobile checkout flow, Fiska gives you the functionality to roll out payment features quickly, confidently, and without breaking your app.

Support for you and your merchants when you need it

Fiska was built by SaaS and payments experts, so we understand the complexities of running a SaaS business. As well as guiding you strategically, we offer technical support for both you and your merchants:

• Level 1 support: We’re hands-on if there’s a payment problem, and we offer multi-channel support.
• Level 2 support: We’re available to talk directly to your merchants on your behalf. If your merchant experiences a payment issue and can’t accept debit and credit card payments for an entire trading day (or more), they’ll direct their anger at you—since you’re the one they’re paying! Normally you’d have to submit a ticket with your payment provider that could take days to resolve. In contrast, Fiska will contact your merchant directly and talk them through how to resolve their issue within 24 hours.

We make customer support simple.

You’ll only ever talk to the same people, so you’ll build a strong relationship with our team and won’t have to re-explain your business every time you need help. We can chat via Slack, phone, or email: no need to raise a ticket and wait several business days.

Want to get set up with Fiska? Book a no-obligation call with our experts.

 

Rainforest

Rainforest is an embedded payments provider for software platforms, subscription services, and vertical SaaS. The company uses interchange-plus pricing, allowing platforms to generate revenue by marking up the base rate.

Rainforest supports omnichannel payments as well as providing a fully white-labeled experience, though their website makes no mention of level 2 support (support for merchants), nor does it specify that they offer universal tokenization.

Rainforest uses a fixed markup, meaning there’s no revenue share. Usage-based fees are not publicly listed, and may complicate budgeting for small businesses.

Tilled

Tilled is a Payfac-as-a-Service that was built to monetize marketplace platforms and SaaS. Tilled provides hosted solutions for onboarding and payment processing, which require minimal coding and are ideal if your team has limited resources or prefers a quicker setup.

Tilled uses fixed-rate or interchange-plus pricing, and they offer revenue share at either 70% or 90% if you choose a fixed-rate plan. Businesses looking for flexibility to scale or switch without lock-in penalties might be drawn to Tilled’s promise of no long-term contracts.

Like Fiska and Cardknox, Tilled is white-labeled and supports omnichannel payments, including card-present and card-not-present. It offers detailed documentation for onboarding, reporting, and chargebacks, but their website doesn’t clarify whether Level 2 support or universal tokenization is included.

Tilled charges a High Volume Dispute fee, which is charged to all merchants with a high dispute rate (regardless of the outcome of individual disputes). The exact amount of this fee is not publicly disclosed on Tilled’s website.

Is Payfac-as-a-Service right for you? Read more: Payfac-as-a-Service VS Payfac-in-a-Box

Finix

Finix is a full-stack payment processor that serves software platforms, marketplace platforms, and individual businesses of all sizes. Their user base is very broad, and it’s worth noting that their solution isn’t specifically designed for SaaS.

Users can choose either flat-rate or interchange-plus pricing, and like the other Cardknox alternatives on this list, Finix is white-labeled and supports omnichannel payments. While they offer integrated payment onboarding, reporting, and chargebacks, their main differentiator is their advanced analytics tools, which help merchants track transaction trends and optimize workflows.

Users can set up custom fee profiles for different merchants, including volume-based discounts or specific charges based on transaction types. While useful, setting up custom fee structures may require technical expertise, especially as Finix’s API documentation is extensive.

Finix is flexible, though it does lack niche risk models tailored to vertical industries like healthcare or legal, which means users may need to invest additional effort into customizing Finix’s tools. Also, their website doesn’t specify if Level 2 support or universal tokenization is offered.

Stax

Primarily built to accommodate retail and e-commerce businesses, Stax serves as both a PayFac-as-a-Service and an embedded payments platform (through its Stax Connect offering). For those interested in Stax Connect, it’s recommended to contact Stax directly to obtain a customized quote that aligns with your specific integration and business requirements.

It offers a fully white-labeled experience and supports omnichannel payments across various payment methods. While their credit card payouts are typically available within 48 hours, ACH payouts from Stax take around 3-5 days to clear, which impacts cash flow for SMEs. In addition to this, it’s unclear from their website whether they offer level 2 merchant support or universal tokenization.

Choose a payment partner specifically built for SaaS

While there are many strong payment services on the market, we believe that Fiska is a solid choice for SaaS companies looking to take control of their payments experience. Built specifically with SaaS in mind, our platform gives you the highest level of control over payments and pricing. We become an extension of your team, supplying transparent pricing, easy setup, and support that goes above and beyond.

With Fiska, you’re not just choosing a provider: you’re gaining a partner who’s fully invested in your success.

Are you a SaaS company that wants to chat with an embedded payments expert? Get in touch with Fiska’s CEO.

Sources:

1. https://solapayments.com (formerly Cardknox)
2. https://www.rainforestpay.com/
3. https://www.tilled.com/
4. https://finix.com/
5. https://staxpayments.com/

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FAQs about Sola Payments alternatives