Shared Budgets is now available in all Bing Ads applications, including the Web UI, API, Editor (read-only) and mobile apps (read-only), to help advertisers simplify how they manage daily budgets, eliminating the need to spend extra time setting up and recalculating individual campaign budgets.
Bing notes, that Shared Budgets is currently not supported with Import and Google Sync. for example, when a campaign is using a Shared Budget on Bing Ads, and you try to import for the same campaigns from AdWords, "a campaign's budget property will not be updated on the Bing Ads side," bing explained. Adding, this feature will be releasing beginning of 2017, as they're working to make it.
Benefits of Shared Budgets in Bing Ads, "advertisers can have a single budget to be used by all campaigns under or by a subgroup of campaigns under an account." As well as "it reduce time spent manually calculating how to allocate budget individually amongst a significant number of campaigns."
"Shared Budgets can also automatically allocate your unutilized budget budget to campaigns that are performing well."
How Does It Work? Say you have a budget of $20 to be used uniformly between two campaigns every day. On a given day, Campaign A spends only $8 (of its $10 budget) because it got fewer impressions and clicks than usual. Using Shared Budget, "if Campaign B is performing well Bing Ads will automatically allocate that unutilized $2 to Campaign B," bing explains. "This will increase the chance that any unutilized budget being used to drive more traffic."
This feature is available as a Shared Library in the Web UI as seen below: