Once you’ve decided on the cost model for your Facebook ads, your minimum bids, and your maximum daily budget, you will need to decide for what length of time you want your ads to run.
When you first create an ad on Facebook, your settings are defaulted to show your ads continuously, with no end date. During the days your ads are active, they will be shown to your Facebook target audience until your budget for that day runs out. Your budget will be exhausted when your ad reaches a certain number of impressions if you pay per thousand impressions or a certain number of clicks if you pay per click. Every day your budget is reset, and your ads will stop running only when you pause or delete the campaign. To help you target your ads towards more specific events, or as a way to test ads, Facebook gives you the option to show your ad only for a specific period of time. You define this time period when you create the ad by specifying a specific start date and time and an end date and time.
Whether you want to run your ads continuously or for a specific period of time depends on the type of ad you are running. You may want a branded general purpose ad to run continuously, although it could be costly if you spend your daily budget every day until you decide to pause or end your campaign. Obviously, it makes more sense to choose a specific start and end date when an event is announced for a limited time. In that case, be sure to run your ad long enough before the event to give it maximum exposure.
Choosing a specific time period to display your ads is useful if you are on a small budget or want to test the variations of the ads against each other, such as ads with different text or different landing pages. By running your ads for specific periods of time, you can separate them into different test groups that you can then compare.
