Webhook vs Polling: What's the Difference and Which Should You Choose?

When connecting two systems — whether it's a payment gateway to an accounting system, an ERP to e-commerce, or a CRM to a marketing tool — one question always comes up:

"How do we know when there's new data to sync?"

There are two main approaches: Polling and Webhook. They're fundamentally different, and choosing the wrong one can make your system slow, expensive, or unnecessarily complex.

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What Is Polling?

Polling is when your system repeatedly asks a remote server "is there any new data?" Think of it as calling a restaurant every 5 minutes asking "is a table available yet?"

How it works:

Client → GET /orders?updated_after=2026-03-27T10:00:00 → Server
Client ← { orders: [] } ← Server  (nothing new)

... 5 minutes later ...

Client → GET /orders?updated_after=2026-03-27T10:00:00 → Server
Client ← { orders: [{ id: 123, status: "paid" }] } ← Server

Pros of Polling:

• Simple to implement — just a loop + API call
• Client controls its own timing
• No public URL required for the server to call
• Easy to test

Cons of Polling:

• Wasteful — most responses are empty
• Higher latency — new data may wait until the next interval
• Short intervals can hit API rate limits

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What Is a Webhook?

A webhook is when the remote server notifies your system immediately when an event occurs — no need to ask first. Like leaving your phone number at a restaurant so they call you when a table is ready.

How it works:

1. You register a URL: POST /register-webhook { url: "https://your-app.com/hooks/payment" }
2. When a payment succeeds:
   Server → POST https://your-app.com/hooks/payment → You
   Body: { event: "payment.completed", orderId: "123", amount: 5000 }
3. Your system processes it immediately

Pros of Webhooks:

• Real-time — data arrives the instant the event occurs
• Resource efficient — no wasted requests
• Scales better for high-volume events

Cons of Webhooks:

• Requires a public HTTPS URL (complicates local dev)
• Harder failure management — missed events if your server is down
• Must verify signatures for security
• Harder to debug than polling

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Webhook vs Polling: Direct Comparison

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When to Use Each

Use Webhook when:

• Payment confirmation — Must know immediately to fulfill an order
• Inventory changes — Real-time stock updates across all channels
• Status updates — Shipping status from logistics partners
• User-triggered events — Form submissions, new messages, comments

Use Polling when:

• Nightly batch sync — Pull daily sales/orders for report generation
• API provider doesn't support webhooks — Legacy systems with REST-only APIs
• Internal tools that don't need real-time — Dashboards refreshing every 15 minutes
• Development/testing — Easier to debug

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Webhook Best Practices

1. Respond 200 OK Immediately

Webhook endpoints should receive data → save to queue → reply 200 immediately, then process later. If processing takes too long before responding, the provider may timeout and resend.

2. Verify the Signature

Most providers attach an HMAC signature in the request header. Always verify it before processing to prevent spoofed requests:

const signature = request.headers['x-stripe-signature']
const isValid = verifyStripeSignature(body, signature, process.env.WEBHOOK_SECRET)
if (!isValid) return res.status(401).send('Invalid signature')

3. Implement Idempotency

Providers may send the same event multiple times (retries). Design your system to handle duplicate events without side effects. Use eventId as a unique key for deduplication.

4. Log Every Incoming Event

Store raw payloads of every webhook received. Invaluable for debugging.

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The Hybrid Approach

In real production systems, both methods are often used together:

• Webhook for real-time updates in normal operation
• Polling as a fallback every 15–30 minutes to catch missed events from server downtime

This architecture keeps the system both responsive and reliable.

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Conclusion

There's no universally correct answer between webhook and polling — it depends on your use case, latency requirements, and acceptable complexity.

If you need real-time and the provider supports it → Webhook is the answer.
If you need simplicity or the API lacks webhook support → Polling still has its place.

The Adowbig team designs and implements integrations between any type of system — from payment gateways to ERPs and third-party platforms.