It takes around 24 hours for the counter at the top of the Contacts module to update. If you want to make sure your contacts were added properly, you can:
- Check your Contact Import Status under Import History (if you imported a CSV).
- Scroll to the bottom of the contacts page and check the total contacts at the bottom left of the table:
- Spot check a few addresses you know are new additions.
- Create or test a relevant segment and view how many subscribers exist in that segment.