Why are my sequence emails queued and not sending?

Last updated: May 4, 2026

If your sequence emails are stuck in the queue and not sending out, there are several potential causes to investigate. This issue can affect all types of sequences, including audience sequences, campaign deployments, and automated email series.

Check for US Holidays First

The most common overlooked cause of emails not sending is the holiday setting. If no emails are going out at all on a given day, check if the current date is a US holiday.

By default, the holiday setting prevents all email sending on US holidays and overrides all other configurations, including:

  • Prioritization settings

  • Backlog configurations

  • Sequence timing

  • Send schedules

This can make it appear that other troubleshooting steps (like adjusting prioritization) aren't working, when in reality the holiday setting is blocking all email activity.

Other Common Causes

If the current date is not a holiday, consider these additional factors:

  • Send time restrictions: Check if your sequences are configured to send only during specific hours and on business days. Emails will only send during your configured sending window. If you add a contact to a sequence outside your configured send hours (e.g., after 4 PM when your schedule ends at 4 PM), the email will be queued until the next available send time, typically the following business day.

  • Daily send limits: Each mailbox sends up to 25 emails per day with a 4-8 minute throttle between sends. Verify if you've reached your daily email sending quota.

  • Mailbox backlog: Sending follows a first-in-first-out (FIFO) queue across all sequences sharing the same mailbox. A backlog will automatically reschedule emails into future days.

  • Sequence pausing: Confirm that your sequences haven't been accidentally paused

  • Manual task completion: If your sequence's first step is a manual task, it must be completed before automated emails can send.

  • Audience targeting: Ensure your target audience still meets the sequence criteria

Advanced Manual Email Task Troubleshooting

While the published article covers that manual tasks must be completed before emails can send, there's an important distinction that often confuses users: approving a manual email task is not the same as completing it.

The Approval vs. Completion Issue

Many users believe that clicking "approve" or reviewing a manual email task means it's complete, but the email will remain queued until you perform the actual completion action. This creates confusion when users see emails still stuck in queue despite having "approved" them.

How to Properly Complete Manual Email Tasks

  1. Locate the manual email task in your sequence workflow

  2. Open the task details (don't just approve from the overview)

  3. Perform the required completion action - this might involve:

    • Clicking a specific "Complete" or "Send" button

    • Filling out required fields

    • Confirming the email content

  4. Verify the task status changes from "pending" to "completed"

Simply reviewing or approving the task from a dashboard view typically won't trigger the actual completion that releases queued emails.

Quick Check

If your emails are queued and you have manual email steps, revisit each manual task and ensure you've performed the full completion workflow, not just the approval process.

Quick Resolution Steps

  1. Check if today is a US holiday and if holiday sending is disabled

  2. Review your sequence settings for any paused campaigns

  3. Verify your daily sending limits haven't been exceeded

  4. Confirm your send time windows allow for current time

Increasing Send Capacity

If you're experiencing persistent backlogs, you can implement these solutions:

  • Add additional mailboxes: Route your sequence to multiple mailboxes to increase daily sending capacity beyond the 25 emails/day per mailbox limit

  • Pause lower-priority sequences: Temporarily pause sequences sharing the same mailbox to free up capacity for higher-priority campaigns

  • Reassign Step 1 enrollments: Move queued Step 1 enrollments to a mailbox with less backlog (note: this only applies to Step 1 emails)

By checking the holiday setting first, you can quickly identify and resolve the most common cause of completely blocked email sending.