Multi-advertiser ads is a checkbox at the ad level in Meta Ads Manager, and on a new ad it's on unless you untick it. When it's on, Meta can show your ad inside a single unit alongside ads from other businesses, and Meta says your creative may be resized or cropped to fit. We untick it on every ad we build. The ad you designed should be the ad people see.
What multi-advertiser ads actually are
Meta's Business Help Centre describes an ad unit as a container that displays several ads together. With multi-advertiser ads on, your ad can be placed in one of those containers next to ads from other businesses, personalized to the viewer, and not necessarily related to yours. It can happen in these placements:
- Facebook Feed, Video on Facebook, Facebook Stories and Facebook Reels
- Instagram Feed and Instagram Reels
On Instagram, tapping your ad in the unit opens it in a full-size Feed or Reels view, where people can keep scrolling through more ads. On Facebook, a tap goes to your destination. Meta is also gradually introducing a version for instant forms: your form can appear alongside other businesses' forms, and the page after someone submits can show ads for other products and services.
It's on unless you turn it off
Meta's documentation makes this a default rather than a choice:
- New API-created ads. Meta's Marketing API documentation says ads created through the API on or after August 19, 2024 are enrolled unless they explicitly opt out. In the Ads Manager builds we've walked through on calls, the box was already ticked.
- Boosted posts. Ads boosted from a Facebook Page or Instagram profile are opted in by default.
- Existing ads. Meta warns that multi-advertiser ads may be turned on automatically for existing ads unless they were explicitly opted out.
To turn it off on one ad: at the ad level, go to Ad setup and untick the box next to Multi-advertiser ads. To fix a whole account: in the Ads tab, select the ads, click the arrow next to Edit, choose Multi-advertiser ads, and untick the box next to Edit all selected ads.
Why we untick it
On a mentoring call, we built a new ad with a jewelry brand. Once the creative was in, we scrolled down to the multi-advertiser box and unticked it. The reasoning we gave: in a shared unit, your images, video and headline get cropped or shrunk to fit a smaller slot, so you're paying to show the brand in a cramped space next to other businesses. For a product that sells on how it looks, that's the wrong trade. We did the same on a separate call building a restaurant's website conversion ad.
Meta's case for the feature is that it reaches people who are looking to go deeper in their shopping journey. That may suit some catalog-style advertisers. Our read is different for most of the accounts we run: when the creative carries the brand, or a B2B buyer needs to land on your page and read it, a cropped tile beside someone else's offer isn't the impression you're paying for.
If you want proof instead of our opinion
Test it properly. Two copies of the same ad in one ad set won't get an even split, so use Meta's A/B test tool, as we explain in two ad sets in one campaign is not an A/B test. Judge the result on cost per purchase or qualified lead, not on clicks or reach. Until you've run that test, leave the box unticked.
The takeaways
- Multi-advertiser ads can place your ad in a unit with other businesses' ads, and Meta says your creative may be cropped to fit.
- It's on by default for new API-created ads and boosted posts, and may be switched on for existing ads that weren't opted out.
- Untick it at the ad level under Ad setup, or in bulk from the Ads tab.
- If you think it helps your account, prove it with a real A/B test on your actual conversion event.
Common questions
What are multi-advertiser ads on Meta?
Multi-advertiser ads let Meta show your ad inside an ad unit that also contains ads from other businesses, on selected Facebook and Instagram placements. Meta's Business Help Centre says the ads in the unit are personalized to the viewer, may or may not be related to each other, and that your creative may be resized or cropped to fit the unit.
How do I turn off multi-advertiser ads?
In Ads Manager, open the ad, go to Ad setup and untick the box next to Multi-advertiser ads. To change several ads at once, select them in the Ads tab, click the arrow next to Edit, choose Multi-advertiser ads, and untick the box next to Edit all selected ads.
Are multi-advertiser ads on by default?
Effectively, yes. Meta's Marketing API documentation says new API-created ads created on or after August 19, 2024 are enrolled unless they specify an opt-out, its Business Help Centre says ads boosted from a Page or Instagram profile are opted in by default, and it warns that multi-advertiser ads may be turned on automatically for existing ads that weren't explicitly opted out.
Which placements show multi-advertiser ads?
Meta lists Facebook Feed, Video on Facebook, Facebook Stories, Facebook Reels, Instagram Feed and Instagram Reels. On Instagram, tapping an ad in the unit opens it in a full-size Feed or Reels format. On Facebook, a tap goes straight to the advertiser's destination.
Do multi-advertiser ads apply to lead ads?
Meta is gradually introducing a version for instant forms. When it applies, your instant form can appear alongside forms from other businesses, and the page shown after someone submits can surface ads for other products and services, so it may not be available in every account yet.