The described technology is generally directed towards combining (multiplexing) two or more pending data requests for the same data item into a single request that is sent to a data providing entity such as a back-end data service. Described is maintaining a mapping of the requests to requesting entities so that a single response to a multiplexed request having data for a requested data item may be re-associated (de-multiplexed) to each requesting entity that requested that data item. Also described is batching a plurality of requests, which may include one or more multiplexed requests, into a batch request sent to a data providing entity.