The number of recipients of my campaign changed after I sent it. Why?

You expected a certain number of contacts to receive your campaign but when you checked the associated tracking reports, the number changed. How can that be?

Outlined below are common possibilities for a recipient count to change when a campaign is sent.

1. The campaign was setup to be sent to more than one segment or category. The system will dedupe the recipient list of a campaign if the same recipients are found to be in more than one of the groups assigned to receive the campaign. This will result in a reduction of the final recipient count. 
   
   
2. The campaign was setup to use a suppression list, suppress a segment or category, or suppress recipients of a campaign that was already sent. In Step 3 of the campaign setup process there are suppression settings. If any of these settings were invoked, a reduction in the final recipient count would be seen.
   
   
3. The campaign was setup to use a random sample size. Also in Step 3 of the campaign setup process there is a setting to set a maximum number of recipients. If this setting is invoked, the recipient count would be capped and the number set. 
    
4. Account administrators have a setting enabled that will email them a copy of every regular sent campaign from the account. You will find this setting upon viewing an account administrator record. If you find that one or more admins have this setting enabled, the recipient count of your campaign will increase.
   
   
5. The contacts who received the campaign have multiple records in a custom table and therefore received multiple copies of the campaign. This would also require a campaign setting be enabled to allow duplicates to be sent. This will result in an increase of the final recipient count.
   
   

Notes

1. The mail log can be a good place to start investigating why recipient counts changed. One way to access the log of a sent campaign is in the Tracking Statistics report. Open the tracking statistics report, locate the campaign(s) in question, and click the mailingID listed on the far left. This will open a "View Outgoing" page. Click "Log" from the left-side menu. Scroll through the log to see if anything stands out. An example log:
   
   
   
   
2. If you have ruled out all of these possibilities, please contact our Support team for assistance.