Send Volume & Rate Limits
Two controls let you bound a campaign's or journey's output:
- Volume limit - a hard cap on how many sends (or journey entries).
- Rate limit - a throttle on how fast messages go out (messages per minute).
These are separate from frequency capping. It helps to think of three independent axes:
| Control | Scope | Answers |
|---|---|---|
| Frequency capping (workspace touching rules) | per user, per period | "Has this user gotten too many messages this week?" |
| Volume limit | per campaign / journey, total | "Have we sent / enrolled N in total?" |
| Rate limit | per campaign / journey, per minute | "Are we sending faster than N/min?" |
How they behave
- Volume limit → a counter, not a wait. Once the cap is reached, the remaining
recipients are skipped (they show up as
volume_capskips in analytics). It never delays anyone. - Rate limit → a wait at the send step. Under the cap, messages go the moment they're scheduled. Over it, sends are delayed so they release at the set pace - nothing is dropped, it just spreads out.
Campaigns
In the campaign composer, open Advanced delivery options (in the Delivery step):
- Send volume limit - turn it on, set Maximum sends, and pick a cadence:
- Lifetime of campaign - the cap is cumulative across every recurring send (the running total is stored durably, so it never resets until you duplicate the campaign).
- Each scheduled send - the cap resets for every recurring occurrence.
- Send rate limit - turn it on and set Max messages / minute. The batch is spread over time to hold that rate.
Journeys (Canvas)
In the canvas Settings:
- Entrance limit - cap how many users may enter the journey. Set Maximum entries
and a cadence:
- Lifetime of journey - never resets.
- Each scheduled send - resets per scheduled run. Beyond the cap, enrollment is skipped. This applies to every entry path - both scheduled/segment enrollment and event-triggered entry. (Event-triggered entry is continuous and has no "scheduled run", so it always counts against the lifetime counter, whichever cadence is selected.)
- Rate limit - throttle how fast users receive messages in the journey:
- All channels (shared budget) - one rate across every channel, or
- Per channel - an independent rate per channel (e.g. push 5,000/min, email 500/min). Because a journey sends continuously, the rate limit makes a message wait at the send node until the rate allows it.
Notes
- All four controls are opt-in - off by default, so nothing changes until you enable one.
- They compose with quiet hours, frequency caps, and send-time optimization (a send waits for whichever constraint is latest).
- Volume-capped and rate-deferred recipients are decided before the send, so they don't count against per-user frequency limits.