When you first launched payments, a flat rate made life simple. You knew what every transaction would cost without becoming a payment expert overnight. Fast forward a few years and millions of dollars in processing volume, and that simplicity starts creating financial friction.

You might have decided you want to move away from flat-rate pricing. Fiska can help. We combine a transparent interchange cost basis with flexible merchant pricing, true revenue sharing, and strategic support as your payment model evolves.

The flat-rate pricing downside for high volume merchants

Flat-rate pricing packages three fee components into a single number. It bundles card network interchange, card brand assessment fees, and processor markups together into a single percentage. Early on, paying a single rate keeps billing predictable.

Volume changes things though. A small difference in pricing economics barely registers when your software processes $50,000 a month. When annual processing volume reaches tens or hundreds of millions of dollars, those same basis points translate into real money. For example:

Annual payment volume	0.10% (10 bps) margin difference
$10,000,000	$10,000
$100,000,000	$100,000
$500,000,000	$500,000

As payments evolve from a basic customer feature into a primary revenue driver, you might want more visibility into your unit economics and answers to questions like:

• What does payment processing actually cost our company on every transaction?
• What rates are our merchants paying for card acceptance?
• What margin exists between processing costs and merchant fees?
• What portion of that margin does our platform keep?
• Can we adjust pricing when different merchant segments carry different costs?

Read more: When is it time to move away from Stripe?

Signs that flat-rate pricing might not be the best fit anymore

Your processing volume doubles year over year. However, your payment margin doesn’t move an inch. If that sounds familiar, your commercial agreement hasn’t kept pace with your growth, and it’s worth checking whether you’re ready for a change.

Here’s what that usually looks like in practice:

• Your economics haven’t budged, even though your volume has. You’re paying the same bundled rate today as when you were a fraction of your current size. Flat margins mean your processor is the one cashing in on your growth, not you.
• You can’t actually see where the money goes. Without line-item visibility into interchange fees and network assessments, your finance team is flying blind on true unit economics and has no way to know if a different model would do better.
• One rate no longer fits everyone you serve. A restaurant doing $200,000 a year and an enterprise account doing $3 million have nothing in common, payments-wise. High-volume merchants expect pricing that reflects their volume, and a one-size-fits-all rate is a good way to lose your best accounts to someone who’ll offer them a better deal.
• Payments have transformed from a feature to a revenue line. It’s no longer just about reducing churn: you want payment volume generating real recurring revenue, which makes your processor’s revenue share arrangement a strategic decision, not a footnote.
• You’re thinking bigger than your current setup. As payments become core to your business, questions like “is an ISO or PayFac model better” start showing up. What you need at that point is a partner who can grow with your roadmap, not one you’ll outgrow and have to rebuild around in 18 months.

Read more: PayFac vs. ISO: Choosing the right model for your platform

What to look for when replacing flat-rate payment processing

Ditching flat-rate pricing should buy you more financial control, not just a marginally better bundled rate. As you look at embedded payment solutions, here’s what actually matters:

• A true, interchange-based cost basis: You need to see raw card network fees, assessment costs, and processor markups as separate line items, not one blended number. That’s the only way to build pricing around real unit economics instead of educated guesses.
• Full control over merchant pricing: You should be able to set rates by industry vertical, transaction volume, or customer tier so you can stay competitive without cutting into your margin.
• A commercial model that rewards your growth, not your processor’s: Look closely at how the spread between wholesale cost and merchant pricing gets split, and who controls it. As your merchants process more, that upside should flow to you instead of padding your processor’s margins.
• More than one way to monetize payments: Different products may call for different approaches: transaction-based margins, processing bundled into your subscription, or payments sold as a standalone feature. You want a partner flexible enough to support whichever fits.
• A partner who thinks past the transaction: Eventually you’ll hit real structural questions: stay an integrated software vendor, become a Payment Facilitator, or operate as an ISO? Each comes with its own regulatory and operational tradeoffs. Fiska CEO Patrick Huynh has pointed out that many platforms rushed toward becoming a PayFac a few years ago to speed up onboarding and gain more control over funds flow, only to find that “the operational burden, compliance requirements, and costs often outweigh the benefits.” Find a partner who’ll help you figure out when, or if, a shift like that actually makes sense for you.

How Fiska gives you more control as you move beyond flat-rate pricing

Leaving flat-rate pricing behind should get you more than a slightly different number on your statement. It should get you real visibility into your costs, real control over what merchants pay, and a real shot at turning payments into revenue instead of just overhead. That’s what Fiska is built around. With Fiska, you can:

• See what processing actually costs. No more working backward from a bundled flat rate and guessing at the math. Fiska shows you the real cost basis at interchange, so you can see where your margin actually comes from and price around real numbers instead of estimates.
• Set pricing around your merchants, not one rate for everyone. Your merchant base isn’t uniform, so why should your pricing be? Fiska lets you configure rates by merchant, vertical, or segment, with tighter pricing where merchants are price-sensitive and a healthier margin where they’re not.
• Capture more of the upside as you grow. Fiska runs on a true revenue-share model where you set merchant pricing above interchange and keep a real cut of the margin. As your merchants process more, your payment revenue grows right along with them.
• Decide how payments fit into your business. Earn transaction-based revenue, fold payments into your subscription, or sell it as a standalone feature – Fiska doesn’t lock you into just one lane.
• Go as far as makes sense for you. Outgrowing flat-rate pricing doesn’t mean you have to become a PayFac or ISO overnight. Fiska gives you strategic guidance as you grow, so you can weigh the tradeoffs before you take on more than you need to.

Choosing a payment model that scales with you

Flat-rate pricing helps early-stage platforms launch quickly, but maturing software businesses need visibility and margin control as transaction volumes scale. Moving to an interchange-based model with a provider like Fiska gives you the flexibility to price competitively, retain more profit, and turn processing into a recurring revenue stream.

FAQ

What’s the difference between flat-rate and interchange-plus pricing?

Flat-rate pricing charges a fixed fee for every purchase regardless of the underlying card type or processing method. Interchange-plus pricing itemizes the exact wholesale interchange fee charged by the card network, the network assessment fee, and the processor markup separately on every transaction.

When does it make financial sense for a software platform to switch away from flat-rate processing?

Switching makes financial sense when your annual processing volume grows large enough that small basis-point savings represent substantial revenue or when you serve diverse merchant tiers with varying price sensitivities.

Do software platforms need to become a PayFac to set custom merchant pricing?

No. Software platforms don’t need to take on the regulatory burden, compliance costs, and financial liability of becoming a PayFac to control merchant pricing. Partnering with an embedded payment platform that offers interchange-based pricing allows software companies to set custom rates and retain margins without operating as a registered PayFac.