The lifetime budget is the total amount that you are willing to spend on one Sponsored Brands campaign for as long as it runs. Once your campaign has reached the lifetime budget limit that you have set, it will stop running ads.
The minimum amount that you can set for a lifetime budget is £100. You will be charged periodically during your campaign until the campaign’s entire lifetime budget is spent. Budgets are spent as quickly as possible and your budget will not be paced throughout the day. This means that a smaller budget could be spent in a few minutes if there are a large number of shoppers interested in your advertised products. This system allows you to benefit from high traffic periods.
You can’t switch between a daily budget and a lifetime budget after you have selected one for a particular campaign. To change your budgeting method for a Sponsored Brand, copy your campaign and create a new one.
For example, if you set your lifetime budget to £1,000 for a campaign running for 10 days, Amazon will deliver up to £100 worth of clicks per day. If you receive £90 in clicks on the first day, the budget for the next day will be £110 to make up for not reaching yesterday’s budgeting threshold. Once you reach your cap of £1,000, your campaign will stop serving ads.