Positioning in currently deployed LTE networks is made via a combination of enhanced cell identity (E-CID), observed time difference of arrival (OTDOA) and global navigation satellite system (A-GNSS) information. Both simulations and field trials indicate acceptable performance for outdoor users. However, today the majority of the connections to cellular networks are established from terminals located indoors. This paper provides baseline positioning performance results based on the 3GPP 3D MIMO deployment and propagation model that has been adopted in the 3GPP Release (Rel.) 13 study item on indoor positioning enhancements. Horizontal and vertical accuracies are investigated for both outdoor-only and outdoor-indoor network deployments.