For a standard sample, a maximum of 3 ads can be uploaded in the one project
For self-serve projects, the number of ads you can include in set up depends on the target sample you have requested. Because each ad is run with a unique group of respondents, you may be limited in the number of ads allowed in a single project.
Once your requested sample is made available to you, you will see a note regarding the maximum number of ads that can be tested using that sample:
If you would like to test more than the maximum number of ads allowed in a project, you can create additional projects for any remaining ads. Please note that this can cause longer fieldwork times.