Payment gateway integration for Laravel, PHP and WooCommerce

Payment gateway integration means connecting your website or application to a provider that takes the money, then making your own system react correctly to everything that provider reports: success, failure, pending UPI payments, disputes, refunds and renewals. The visible part is a pay button. The invisible part is the order state machine behind it.

This service suits businesses with a Laravel, CodeIgniter or core PHP application that need to start taking payments, SaaS products adding paid plans, WooCommerce stores that want a different or additional gateway, and teams whose current integration loses orders or marks unpaid orders as paid. It also suits Indian businesses that need UPI, netbanking and wallets alongside international cards.

It is not for you if a hosted payment link or a no-code store already does what you need. If you sell a handful of products and the gateway's own payment pages are enough, use them: I would rather tell you that on a short call than build something you do not need.

Payment bugs are rarely exotic. They come from shortcuts that look fine in testing and fail with real customers, slow networks and gateway retries. Here is what I build against:

• Trusting the browser redirect. A customer can close the tab before the success page loads, or tamper with the query string. Payment status is confirmed on the server, by verifying the gateway signature or fetching the payment from the gateway API, and by the webhook.
• Skipping signature checks. Razorpay signs the order and payment IDs with HMAC SHA256 using your key secret. Stripe signs webhooks in the Stripe-Signature header against the raw request body, which breaks if middleware parses the JSON first. PayU uses a SHA-512 hash with your salt, including a reverse hash on the response. Cashfree signs webhooks with a timestamp. Each one is verified before anything changes in your database.
• Processing the same event twice. Gateways retry webhooks, and the redirect and the webhook often arrive at the same moment. I store each event ID behind a unique index and lock the order row inside a database transaction, so an order is marked paid once and stock or credits are granted once.
• Money stored as floats. Amounts go to gateways in the smallest unit (paise or cents) as integers, and are stored as decimals, so rounding never creates a one-paisa mismatch on an invoice.
• No idempotency on outgoing calls. Refunds and charges sent to Stripe carry an Idempotency-Key, so a timeout followed by a retry does not refund a customer twice.
• Nobody reconciles. A scheduled job compares your payments with the gateway's settlement data and flags anything that does not match, before your accountant finds it.

The right gateway depends on where your customers are, which currencies you charge in and whether you bill once or every month. Many businesses end up with two: an Indian gateway for domestic customers and Stripe or PayPal for international ones. I wrote a longer comparison in Razorpay vs Stripe for Indian businesses.

For a Razorpay integration in website checkouts aimed at Indian buyers, Razorpay, PayU and Cashfree all support UPI, cards, netbanking and wallets, and each has subscription features. Cashfree is also often chosen for payouts. Stripe is strong for international cards, multi-currency pricing and subscription billing, but new Stripe accounts for India-registered businesses have been invite-only since 2024, so check your eligibility before we design around it. PayPal is worth adding when your buyers are international and already trust it; a PayPal integration in PHP uses its REST Orders API with webhooks for capture and refund events.

For payment gateway integration India-side, also plan for the paperwork: GST on the invoice, the right business category on the gateway account, and RBI e-mandate rules for recurring payments. These affect the build, so I ask about them early.

For a stripe subscription Laravel setup, Laravel Cashier is usually the right starting point: it manages customers, subscriptions, trials, plan swaps and Stripe invoices, and ships a webhook controller you extend. A clean Laravel Stripe integration still needs decisions Cashier cannot make for you: what happens to access when a renewal fails, how long the grace period is, how proration should look on an upgrade, and which events your app must react to.

Razorpay subscriptions work differently: plans and subscriptions are created through its API, the customer authorizes a mandate, and charges arrive as webhook events. Under RBI rules, recurring card and UPI payments need an authorized e-mandate, and larger amounts can need extra customer authentication, so renewals can fail for reasons that have nothing to do with your code. I build the retry, reminder and access logic around that reality, and log every state change so support can answer a customer's question in seconds. If you are building the whole product, my SaaS and MVP development work covers plans, roles and billing together.

Payments are a transactions problem before they are an API problem. My daily work is PHP 8 and Laravel with MySQL transactions, row-level locking, queued jobs, webhooks and signed-request verification, which is exactly what keeps a payment flow correct under load. I also work in CodeIgniter 3 and core PHP, so an older application does not need a rewrite to accept payments properly.

You deal directly with the engineer who writes the code, and I explain trade-offs in plain language: what a webhook failure would mean for your customers, and what I would not build. I am based in India, which helps with Razorpay, UPI and GST details, and I work remotely with clients in different time zones; we agree on update times at the start.

I will not list past payment projects here that I cannot show you. On a call I will walk you through how I would structure your flow, step by step, and you can judge the approach before you commit. The same platform knowledge applies whether the gateway sits in WooCommerce development, a Perfex CRM customization or a custom Laravel app.

There is no flat price, because two integrations that look alike from the outside can differ a lot underneath. After a short call or a written brief I send a fixed quote. These are the things that move it:

• How many gateways, and whether customers choose between them or they split by country or currency
• One-time payments only, or subscriptions with trials, upgrades and failed-renewal handling
• The platform: configuring an official WooCommerce plugin is smaller than a custom flow in Laravel or legacy PHP
• The state of the existing code, especially if orders and payments are already out of sync
• Refunds, partial captures and admin tools for your support team
• Reconciliation reports, GST invoices and accounting exports