Campaign, Ad Group, Ad

Every Reddit ad account is built in three layers: the campaign sets the objective, the ad group sets targeting and budget, and the ad is the creative people see.

You choose the objective once, at the campaign level, and it drives how Reddit optimizes. Inside that campaign you build one or more ad groups, and each ad group holds its own targeting, bid, budget, and schedule. Inside each ad group you place the actual ads. Splitting targeting across separate ad groups is how you keep budgets and reporting clean.

Suppose you run a traffic campaign for a running-shoe store. You create two ad groups: one targeting the marathon-training community, one targeting the interest category for running. Each gets its own budget. When the first ad group returns clicks at half the cost of the second, you know exactly where to move money, because the structure kept them apart.

Do not stuff every audience into one ad group. If you mix five subreddits and three interests together, Reddit optimizes toward the cheapest slice and you cannot tell what actually worked. Separate what you want to compare.

Structure is not paperwork. It is how you read the results.