Make Payments Work In Every Market That Matters
Payment gateway integration for e-commerce and subscription businesses, tested across every payment path before launch.
Payment gateway integration is connecting a checkout or billing system to a payment provider's API so transactions, currencies, and recurring charges process correctly and failures are recovered rather than silently lost.
What is Payment Gateway Integration?
Payment gateway integration is connecting a checkout or billing system to a payment provider's API so transactions, currencies, and recurring charges process correctly, and failures are recovered rather than silently lost.
Skipping the failure cases is expensive in a way that's easy to miss: nobody files a support ticket when checkout fails, they just leave, and a declined renewal can quietly churn a subscriber who never intended to cancel.
It's different from general API integration, which connects systems broadly - payment work carries its own compliance, currency, and recurring-billing considerations that a generic connector doesn't need to account for.
Common problems we solve
Silent checkout failures
Nobody files a support ticket when checkout fails - they just leave and try a competitor instead.
Untested failure cases
Expired cards, unsupported currencies, and out-of-order webhooks never get exercised before launch.
Renewal churn
A failed payment quietly cancels a subscriber who never intended to leave.
Compliance bolted on late
PCI compliance treated as an afterthought instead of built into the integration architecture.
Unhandled currency edge cases
A checkout that works domestically breaks quietly on currency or local payment method assumptions abroad.
Everything covered in this service
Gateway Selection & Setup
Provider evaluation against your markets and volume, with checkout flow implementation and testing.
Multi-Currency & Multi-Market Configuration
Currency and locale-specific checkout logic, with local payment method support where relevant.
Subscription & Recurring Billing
Recurring charge scheduling and proration logic, with plan changes handled correctly.
PCI Compliance Considerations
Architecture that avoids unnecessary handling of raw card data, per provider requirements.
Failed Payment Recovery
Automated retry logic for declined renewals, with dunning communication sequencing.
Our optimization framework
Review
We confirm which gateway actually fits your markets, currencies, and volume before building anything.
Integrate
The checkout flow is connected to the gateway's API, covering the currencies and payment methods relevant to your customers.
Configure
For subscription businesses, we configure renewal scheduling, proration, and plan-change logic.
Test
We deliberately test declines, expired cards, and edge cases most launches skip, before they happen to a real customer.
Build
Retry logic and dunning communication are set up for renewal failures, since some percentage of them are inevitable regardless of setup quality.
Launch
We confirm the integration pattern avoids unnecessary exposure to raw card data before going live.
What actually changes
| Before | After |
|---|---|
| A failed payment is just a lost customer | A failed payment triggers an automated recovery attempt |
| A declined renewal silently cancels the subscriber | A declined renewal triggers retry and dunning outreach |
| International checkout untested for currency edge cases | Currencies and local payment methods tested deliberately |
| Raw card data handled directly by the checkout | Architecture minimises exposure to raw card data |
What we report on
Checkout completion
Measured across the currencies and markets the gateway is configured to support.
Renewal recovery rate
Tracked through the automated retry and dunning sequence for declined renewals.
Payment failure alerts
Reported through gateway and webhook monitoring, not discovered after a customer complaint.
Compliance exposure
Reviewed against the integration pattern used for handling card data.
Tools & platforms
Industries we optimize for
Built for teams like yours
Why choose EASI7
We fix tracking before we touch results
Every engagement starts with the same audit we'd run on our own accounts, so the numbers you're optimizing against are actually true.
One accountable team, not siloed vendors
The same team that does this also owns the rest of your stack - no handoff, no blame-shifting between vendors.
Built for how AI search actually works
Everything we build is structured to be extractable by AI answer engines, not just ranked in a list of blue links.
Reporting tied to your own dashboard
Every number we report ties back to GA4/GTM events you can see directly - not a screenshot from a tool you can't independently verify.
Related Integrations services
Get Your Systems Talking To Each Other
Custom API integration that turns five disconnected tools into one working system.
IntegrationsLeads that land in the CRM automatically, correctly
CRM integration connecting your website, ads, and marketing tools so leads never require manual entry.
IntegrationsYour stack, working as one system
Integration across email, ads, analytics, and automation platforms so data flows without manual exports.
Connect Any Tool - Even the Ones No One Else Will Touch
Custom connectors for the specific tools your business runs on, including the ones nobody else builds for.
How to engage us for this
Project-based
A defined outcome with a start and end date - an audit, a migration, a campaign build, a tracking overhaul. Fixed scope, fixed price, agreed upfront.
Ongoing retainer
Continuous management and optimization once the initial build is live - campaigns, SEO, reporting, and iteration run every month under one accountable team.
Advisory
Strategy and oversight without full delivery - we review what's already running, unblock decisions, and point an in-house or existing team in the right direction.
Common questions
Stripe, PayPal, and most major providers with a documented API. Selection depends on your markets, volume, and existing platform - we'll recommend based on your specific situation rather than defaulting to one provider.
No legitimate integration can guarantee a specific conversion outcome, since checkout completion also depends on pricing, trust signals, and factors outside the payment flow itself. What a properly tested integration does guarantee is that the payment step itself isn't the reason a legitimate transaction fails.
We build using integration patterns that minimise your exposure to raw card data - typically hosted fields or tokenisation provided by the gateway - which reduces your compliance scope. Full compliance certification is a separate process that depends on your broader infrastructure, not just the checkout integration.
A properly built recovery flow retries the charge on a schedule and triggers customer communication (dunning) asking them to update their payment method, rather than cancelling the subscription immediately on the first failure.
A standard checkout integration for a single market and currency typically takes two to three weeks including testing. Multi-currency, multi-market, or subscription billing with recovery flows adds time, scoped based on how many markets and edge cases are involved.
Losing customers at checkout without knowing why?
We'll test your current payment flow across the failure cases most launches skip, before recommending a fix.
Ready to get started?
We usually reply within 24 hours.
Payment Gateway Integration, in detail
Scope, area by area
| Area | What we deliver |
|---|---|
| Checkout Integration | A tested, working payment flow connected to the selected gateway |
| Recurring Billing | Subscription logic covering renewals, upgrades, downgrades, and cancellations |
| Recovery Flow | Automated retry and communication sequence for failed renewal payments |
| Compliance Review | Confirmation the integration pattern meets the relevant PCI requirements for your setup |
How this compares
| Tested Payment Integration | Happy-Path-Only Setup |
|---|---|
| Failed and declined payments are caught and recovered | A failed payment is just a lost customer |
| Renewal failures trigger automated retry and outreach | A declined renewal silently churns the subscriber |
| Multi-currency edge cases are handled deliberately | International customers hit checkout errors nobody tested for |
Most payment integrations work fine in a demo. The difference shows up months later, in the renewal failures and edge-case transactions nobody tested for at launch.