What Is a Campaign, Ad Set and Ad in Meta Ads?

Meta calls these three layers the campaign structure, and you build them in order. First you say what you want (campaign), then who should see it, where, when and for how much (ad set), and finally what they’ll see (ad).

What do you set at each level?

Level	What you set there	What it can contain
Campaign	The advertising objective, such as Traffic; optionally one campaign budget and a spending limit	Several ad sets
Ad set	Audience (location, age, gender and more), budget, schedule, placements, optional bid	Several ads
Ad	Images or video, text, header, call-to-action button and the Facebook Page identity	The creative your audience sees

Meta describes the campaign as the foundation of your ad. Choosing Traffic, for example, optimises the ad to send people to a destination such as your website, app, or Facebook or Instagram shop.

The ad set tells your ad how to run. Because a campaign can hold several ad sets, each one can have different targeting, scheduling and budget options.

The ad is what your audience sees. Meta’s checklist at this level is to upload an image, several images or a video, then fill in details such as the text and header.

How do you build the three levels?

Choose an objective that matches your goal at the campaign level.
Build your audience at the ad set level.
Set the ad set’s budget and schedule.
Set a bid, if you want to; Meta marks this step optional.
Upload your images or video and add the ad’s text and header.

Where does the budget go?

You have three options, according to Meta:

Advantage+ campaign budget: one budget at the campaign level, distributed in real time to the ad sets with the best opportunities. Meta says it’s best suited to campaigns with at least 2 ad sets, and it’s on by default for Sales, Leads and App promotion campaigns.
Ad set budgets: a separate budget for each ad set, which can be spent as soon as delivery opportunities appear for that ad set.
Ad set budget sharing: each ad set keeps its own budget, but up to 20% of the daily budget can be shared with other ad sets.

Because a campaign budget may not be spent equally across ad sets, Meta advises judging those campaigns at the campaign level, not ad set by ad set.

FAQ

Can I change a campaign’s objective after publishing?

No. Meta says you can’t change a published campaign’s objective. If you need a different objective, stop the campaign and create a new one. The same applies to an ad set’s conversion location, which can’t be edited after the ad set is published.

How many ad sets can one campaign have?

With Advantage+ campaign budget, Meta says you can include more than 70 ad sets, but no more than 200, in a single campaign. Above 70, though, the edits you can make after publishing are limited, so large structures are harder to change later.

What must match across ad sets to use a campaign budget?

Meta lists four requirements: all ad sets use the same budget type (daily or lifetime), the same bid strategy, the same optimisation event if the bid strategy is highest volume, and standard delivery. Turning the campaign budget on or off also has a 2-hour minimum gap.