Sending Limits & Queue | Atlas

Atlas Blue enforces limits on how quickly a phone number reaches people it has not messaged before. Nothing else is restricted. The pacing keeps the number looking like a person sending messages by hand, which is what prevents it from being marked as spam.


Limited	Outbound first messages to new contacts
Not limited	Contacts you upload, inbound messages, replies inside an active conversation

Enforced Limits

All limits below apply per phone number:

Limit	Value
Days 0-2	10 new contacts per day
Days 3-7	25 new contacts per day
Day 8 onward	50 new contacts per day
Monthly	600 new contacts
Spacing	1 new contact every 15 minutes
Sending hours	8:00 AM to 8:00 PM in the contact’s local time

The daily allowance ramps up over the number’s first week of sending. Line age counts from the number’s first outbound message, not from when you bought it.

The monthly limit of 600 is the one to plan around. A number sending at full pace reaches 600 well before the month is over, so size your contact lists against the monthly limit rather than multiplying the 50 per day figure across 30 days.

Sending Window

Atlas Blue only sends during your campaign’s sending window, which works the same way as calling windows on voice campaigns:

Setting	Value
Sending hours	8:00 AM to 8:00 PM in the contact’s local time. Nothing sends outside these hours.
Timezone handling	Detected automatically from the contact’s number
Custom windows	Set narrower windows inside the 8:00 AM to 8:00 PM range, including multiple windows in a single day. The range itself cannot be extended.

Messages that come due outside sending hours wait in the queue until the window opens again.

The window and the 15-minute spacing together set your daily pace. The full 12 hour window allows up to 48 sends a day, and an 8 hour window allows 32. At 48 a day a line uses its 600 monthly contacts in about 13 sending days, so narrow the window or shorten your list if you want outreach running evenly through the month.

See Call Scheduling for how windows are configured.

Contact Status

Restrictions lift as a contact warms up:

Status	What applies
Never messaged	Daily limit, monthly limit, 15-minute spacing, and the first message rules
Messaged, no reply yet	15-minute spacing and the first message rules
Replied to you	No limits apply. Links, pricing, and follow-ups send right away.

Once someone replies, they stop counting against any limit. The limits are there to protect cold outreach, and a conversation that is already two-way is no longer cold.

Message Queue

There is no pacing to manage on your side. Queue as many contacts as you like and Atlas Blue releases one every 15 minutes inside your sending window. A message blocked by the first message rules is put back in the queue rather than dropped. Messages to contacts who already replied skip the queue entirely.

Need More Volume?

Every limit above applies per phone number, so adding lines is how you scale. Two lines gives you 1,200 new contacts a month, and five gives you 3,000. Each new line begins its own ramp-up at 10 per day.