Not all contacts importing

Are you using workspaces and partitions? It is likely.

When a lead exists in one partition and a list is imported outside that partition, the lead does not show up in the imported list.

I'm not using either of those functions in my instance. Almost of all of the contacts in question are brand new to my lead database, so there should not be any conflicts from preexisting configurations.

The file size is likely to be well under the limit of 50 MB. We can rule that out.

Is there any non-printable character around line 8000 if you open the CSV in TextEdit (Mac) or Notepad (Windows)?
It can be caused by wrongly encoded UTF-8 characters. 

Hey Matt,

The import log should show you the results I think.  Other reasons might be:

1.  Do you have a ton of duplicates?  It would update/override the existing record with those email addresses, thus only creating one.

2.  Are the email addresses invalid in some cases?  I'm pretty sure Marketo has problems with this on import (might be wrong on that one though because I feel like I've seen them fairly often in other instances).