This article will explain in details how the budget allocation occurs in Ad360 when you have multiple line items in a campaign. At the end of the Article, you fill find tips to structure your campaigns in an optimal way.
How the budget field works for campaigns
The budget field is one of its most important characteristics of a campaign. The budget is a monetary amount that you have entered in the campaign when you created it (or after an edit).
Spending the budget for a campaign is always a primary objective of the Ad360 Pacing Algorithms. This means that Ad360 will always aim at spending the campaign's budget in full between the campaign's start date and end date (goal function).
How the budget field works for line items
Each Line Item in Ad360 also has a budget field. It works differently though than the campaign's budget, because the line item budget represents an upper limit to how much the line item can spend.
Contrary to the campaign's budget field, the line item's budget is not a goal, but only a constraint. This means that Ad360 will not spend more on a line item than its budget value (constraint behavior) but will not aim at spending the line item in full during the start date and end dates of the line item (goal function).
Once a line item spend reaches its budget value, Ad360 will stop bidding for this line item, and thus prevent the line item from spending more. The only purpose of the line item budget is to give you the option to limit how much a certain line item can spend.
Behavior between campaign and line items budgets
Consider that you a campaign (C) with a budget (B), containing several Line Items (L1, L2, L3, ...), each with its budget value (respectively B1, B2, B3...).
The campaign budget B is the most important constraint, meaning that regardless of B1, B2, B3, the total spend of the campaign will never exceed B, even if B1+B2+B3+... is greater than B.
This means that it is not a problem if any of the line item budgets (B1, B2, B3,...) or their sum is greater than the campaign budget B, in that there is no risk of overspending the campaign budget. In practice, and if you don't need to limit the spend for a particular line item, we advise you to each line item budget equal to the campaign budget (B1=B, B2=B, B3=B, ...), which will give full latitude to the Ad360 Pacing algorithms to allocate the spend such that the campaign's performance is maximized.
However, if the sum of all line items budgets is inferior to the campaign budget (B1+B2+B3+... < B), then Ad360 won't be able to spend more than B1+B2+B3+... and won't be able to spend the campaign's budget B in full.
When there are several line items available, whose total spend amount is lower than their budget, the Ad360 Pacing Algorithm will determine how much will be spent by each line item in order to fulfill the campaign budget goal, while maximizing the results based on the campaign's goal.
- Set each line item budget equal to the campaign budget if you don't want to constraint the Ad360 Pacing Algorithms and just want to maximize campaigns' performance.
- Set a lower budget on a line item if you want to restrict how much that line item can spend.
- To ensure the campaign's full delivery, make sure that the sum of its line item's budget is greater than or equal to the campaign budget.