Email Rate Limits
How Appcues protects your domain health by managing hourly and daily sending limits
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Appcues limits how many emails your account can send per hour and per day. This protects your sending domain from being flagged by email providers, which keeps deliverability high. Limits scale automatically as your sending volume grows.
Default limits
New Workflows accounts start with these limits regardless of domain type:
Daily limit: 450 emails
Hourly limit: 113 emails
If you're a new user and notice a delay between when a user reaches an Email node and when the email is actually sent, your daily limit may have been reached. The email will be sent once capacity frees up.
Request higher limits for custom domains
If you use a custom sending domain with established reputation, Appcues can increase your default limits. Email support@appcues.com with your domain's normal daily send count (including emails from all sources — other tools, personal inboxes, and group addresses on the same domain). Appcues will set your limits as a percentage of that total. This request can take up to 48 hours to process.
Auto-scaling
If you consistently hit your daily limit, Appcues automatically raises it. Here's how the algorithm works:
The system looks at your daily send volume over the past 10 days, excluding the four lowest-sending days (to avoid weekends or quiet days from dragging the average down).
Based on the trend, it adjusts:
- Volume went up yesterday — New limit = yesterday's volume + 20%.
- Volume is trending up overall — Current limit holds.
- Volume is trending down — Limit drops to recent average + 20%.
Safety floors apply: the daily limit never drops below 450, and the hourly limit is always at least 113 (set to one quarter of the daily limit).
The algorithm won't make changes until you have at least 10 days of sending history.
In practice, this means your limits grow with your usage. You don't need to request increases manually unless you're ramping up sending on a brand-new account.