Why are my push notifications being sent with a significant delay?

If push notifications are being delivered with a significant delay, especially to a large audience, the most likely cause is a send rate limit (throttling) configured for your project.

How the limit works

A send rate limit caps how many messages Pushwoosh sends per second. It is set per channel: push notifications, emails and SMS each have their own limit, for example 500 messages per 1 second.

The limit applies to the whole project on that channel, including campaigns sent via API, not to a single campaign. If a large push campaign is being throttled, other pushes running at the same time (including small test sends) queue behind it and are delayed too. A limit on another channel, such as email, does not affect push.

How to check and change it

1. Open your project and go to Settings → Message delivery settings.
2. Open the Send rate tab (frequency capping is on the other tab of the same page).
3. Review the limit for Push notifications. Either raise it to a value that fits your campaign volume, or turn the limit off.
4. Click Apply changes and confirm.

See Send rate limits for details.

If the global limit is not the cause

• Per-message send rate. One-time campaigns and Customer Journey elements can use the global send rate, send without it, or use a custom send rate. A custom rate on the message slows that message regardless of the project limit. The same applies to the send_rate parameter in API requests.
• Frequency capping on the same Message delivery settings page.
• Customer Journey settings. If the campaign runs inside a journey, check whether a Silence period (Settings on the journey canvas) or a Best time to send schedule on the message element is holding deliveries back.
• Delivery gateways. APNs/FCM can also delay delivery on their side.