Webhooks Versus Polling: Which Should You Use?
The choice between webhooks and polling shapes how fast, how reliable, and how efficient an integration is. Most robust systems do not choose one; they use each where it is strongest.
When two systems need to stay in step, there are two fundamental ways to move information: the source can tell the destination when something changes, a webhook, or the destination can keep asking the source whether anything has changed, polling. Almost every integration decision about freshness and reliability comes down to which of these you use, and where.
Neither is universally correct. They have different strengths, and understanding them lets you build integrations that are both fast and dependable rather than one or the other.
How each works
With polling, your system calls the source API on a schedule, every minute, every few minutes, and checks for changes since last time. It is simple to build and entirely under your control, but it wastes calls when nothing changed, and it introduces delay equal to the polling interval. Poll too often and you strain rate limits; poll too rarely and your data goes stale.
With webhooks, the source sends your system a notification the instant an event happens. This gives near-real-time updates with little wasted traffic, but it depends on the source supporting webhooks, on your endpoint being reachable and reliable, and on you handling missed or duplicated deliveries. The freshness is better; the reliability engineering is slightly harder.
The trade-offs side by side
- Latency: webhooks are near-instant; polling lags by up to the interval.
- Efficiency: webhooks send only real events; polling mostly returns nothing.
- Reliability: polling always catches up eventually; webhooks can miss a delivery if your endpoint is down.
- Complexity: polling is simpler to build; webhooks need signature verification, idempotency, and fast acknowledgement.
When to use which, and both
Use webhooks when you need to react promptly to discrete events, a payment, a status change, a new record, and the source supports them. Use polling when the source has no webhooks, when you need periodic batch reconciliation rather than instant reaction, or when your endpoint cannot be reliably reachable.
The strongest pattern is often both: webhooks for immediacy, plus a periodic polling pass as a safety net that catches anything a missed webhook dropped. That hybrid gives you near-real-time updates most of the time and guaranteed eventual consistency always, which is exactly what a dependable integration needs.
Building each one well
If you rely on webhooks, invest in the reliability engineering they demand. Verify the signature on every delivery so you know it genuinely came from the source, be idempotent so a duplicate delivery does no harm, and acknowledge quickly while doing slower work asynchronously so the sender does not treat a slow handler as a failure and retry. Plan for downtime too: if your endpoint is unavailable, you need a way to recover the events you missed, which is where a reconciliation pass earns its place.
If you rely on polling, tune the interval to the freshness you actually need rather than defaulting to as-fast-as-possible. Poll only for what has changed since your last check, using timestamps or cursors, so you are not re-reading the whole dataset each time. Respect rate limits and back off when throttled, because an aggressive poller is a common cause of being rate-limited into uselessness.
Whichever you choose, make the integration observable. Log what it receives and does, and alert when it stops. The failure mode that hurts most is neither being told nor asking, an integration that has quietly stopped moving data while everyone continues to trust the picture it once painted.
The deeper lesson is that this is not really a binary choice at all. Webhooks and polling are two tools for the same job, keeping systems in step, and the mature approach uses each for what it does best rather than picking a side as a matter of principle. Reach for webhooks when freshness matters, lean on polling when you need completeness or the source offers nothing else, and combine them when the flow is important enough to deserve both speed and a guarantee. Judge the mechanism by the reliability it delivers, not by which sounds more modern.