Should I run my ads on Instagram only, or on Facebook too?

Facebook and Instagram ads are bought in the same Ads Manager from the same budget. Placements decide where they show: feeds, Stories, Reels, Messenger, the Audience Network of other apps and more. With automatic placements, Meta moves money toward whichever places produce your chosen result at the lowest cost. Restricting placements gives you control but usually raises the price of each result, because you have taken cheaper inventory off the table.

There are good reasons to restrict. A fashion label with a carefully styled look may find that its ads look wrong in some placements, or that the Audience Network brings accidental clicks. A brand whose buyers are clearly young and Instagram-native may see Facebook traffic convert badly. A property developer or school may find the reverse, with parents and family elders responding more on Facebook. The point is to decide from your own results.

To find out, open the breakdown by placement in Ads Manager after the campaign has run for a week or two. Look at cost per result and, more importantly, what happened next: did the Facebook chats book, did the Instagram ones ask for prices and vanish? Remove a placement only when the evidence is clear, not because the owner personally prefers one app.

Creative is the other factor. A vertical Reel built for Instagram will usually also serve on Facebook Reels and Stories. A square post with small text may be weak in both. Make vertical video the default and let the placements follow.