Bing Ads announced they now support call conversions through the offline conversion import method.
Bing noted they have an API for offline conversions and now some call tracking solutions are using it to bring in call conversions.
Specifically Bing wrote:
Call-tracking systems (CTS) can now interoperate directly with Bing Ads and import call conversion data through our Offline Conversion Import tool and related set of APIs. One of our first partners to support the new call conversion capability is CallTrackingMetrics.
Bing added they are eager for more "call-tracking providers using our offline conversions capability to connect call conversion data back to Bing Ads."
Forum discussion at Twitter.