Payment Integration Services
Stripe, PayPal and Plaid integrations for websites, apps and business software. Secure checkout, subscriptions and bank connections from $35 per hour.
Payments That Just Work
We connect your website, app or platform to Stripe, PayPal, Plaid and other payment APIs, with secure checkout, subscriptions, webhooks and syncing to your other systems.
Stripe, PayPal and Plaid integrations built for real web platforms and apps.
WordPress, WooCommerce, Shopify, custom web apps and iOS, Android and Flutter apps.
Card details stay with the provider; designed with PCI DSS requirements in mind.
Payment Integration Services
Checkout, subscriptions, invoices, refunds and webhooks.
PayPal Checkout alongside card payments.
Account linking, verification and transactions for fintech apps.
Online donation forms for nonprofits.
Payments, refunds and payouts in one admin view.
30 days of free bug fixing, then optional maintenance.
Add Secure Payments to Your Website or App
Book a free call and get a clear plan, timeline and written estimate for your payment integration.
What We Integrate
From a simple checkout to a full payment platform:
Checkout and Subscriptions
Card payments, plans, trials and recurring billing.
Mobile App Payments
Payments in iOS, Android and Flutter apps.
Bank Connections
Plaid account linking for fintech products.
Why Choose Three Circle for Payment Integration?
We have built real Stripe, PayPal and Plaid integrations, and we connect payments to the rest of your systems, so orders, accounts and reports stay in sync.
Proven Integrations:
Stripe, PayPal and Plaid, plus many other APIs.
Full-Stack Expertise:
.NET, Node.js, Python, PHP, React, Angular and Flutter.
Ongoing Support:
30 days free bug fixing after launch.
US-Registered Company:
Registered in Sachse, Texas, working with clients across the US.
Transparent Pricing:
Written estimate before work starts; from $35/hr.
Tested Before Go-Live
Sandbox testing of every payment flow.
Payment Integration Services for Websites and Apps
Three Circle connects your website, app or business software to the payment providers your customers already use. We have built Stripe, PayPal and Plaid integrations, along with many other third-party APIs, for web platforms, mobile apps and internal systems. You get secure checkout, subscriptions and bank connections that work reliably, with rates from $35 per hour and projects from $1,000.
Stripe Integration Services
One-off payments, subscriptions and recurring billing, saved cards, invoices, refunds, Stripe Checkout or custom payment forms, and webhooks that keep your orders and accounts in sync.
PayPal Integration
PayPal Checkout and PayPal buttons alongside card payments, so customers can pay the way they prefer.
Plaid Integration (Bank Connections)
Secure bank account linking for fintech apps: account verification, balances and transactions through Plaid, built for apps such as budgeting tools, lending and payments. See our fintech development services.
Donation and Nonprofit Payments
Online donation forms with card payments, as we built for a US non-profit: see the HWCIP case study.
Payments Inside Your Own Software
Payment records, payouts and reconciliation inside your platform, as in our restaurant ordering and POS platform.
What We Build Around Your Payments
- Checkout and payment pages on your website, WooCommerce or Shopify store, or custom web app.
- Subscriptions and memberships with trials, upgrades, cancellations and failed-payment handling.
- Webhooks and syncing so payments update orders, accounts, CRMs and accounting tools automatically.
- Admin dashboards for payments, refunds and payouts.
- Mobile app payments in iOS, Android and Flutter apps.
- Security first: card details stay with the payment provider (tokenization), with HTTPS, access control and logging designed with PCI DSS requirements in mind.
How Much Do Payment Integration Services Cost?
Cost depends on how many providers, payment flows and systems need to be connected:
- Simple checkout (one provider, standard Stripe or PayPal checkout on an existing site): usually from $1,000.
- Subscriptions, webhooks and account syncing: priced by scope after a free call.
- Custom payment platforms (marketplaces, payouts, bank connections with Plaid): estimated after a short discovery.
Our rates start from $35 per hour and every project starts with a written estimate. Try the app cost calculator or book a free call for an exact quote.
Our Payment Integration Process
- Free call: your products, prices, providers and systems.
- Plan: payment flows, webhooks and data you need to keep in sync.
- Build: integration in a test (sandbox) account first.
- Test: successful, failed and refunded payments, subscriptions and edge cases.
- Go live: switch to live keys, monitor the first payments.
- Support: 30 days of free bug fixing after go-live, then optional maintenance.
Related Integration Services
Payments are often one part of a bigger integration. See our software integration services (shipping, CRM, ERP and third-party APIs), AI integration services and eCommerce development.
Want results like these? Tell us about your payment integration project and get a free consultation.
Ready to Add Payments?
Book a free call and get a clear plan and quote for your payment integration.
- FAQs
Frequently Asked Questions
We have built Stripe, PayPal and Plaid integrations, and we work with other payment and banking APIs on request.
Yes. We add Stripe to WordPress, WooCommerce, Shopify and custom web and mobile apps, including subscriptions and webhooks.
A standard checkout on an existing site usually starts from $1,000. Subscriptions, webhooks and syncing with other systems are priced by scope. Our rates start from $35 per hour.
Yes. We integrate Plaid for account linking, verification, balances and transactions in fintech web and mobile apps.
Yes. We build subscription plans, trials, upgrades, cancellations and failed-payment handling with Stripe.
Card details are handled by the payment provider, not stored on your server. We use HTTPS, access control and logging, designed with PCI DSS requirements in mind.
A standard checkout often takes 1-2 weeks. Subscriptions, marketplaces and multi-system syncing take longer and are planned after a free call.
Yes. You get 30 days of free bug fixing after go-live, and optional ongoing maintenance.