This paper proposes an analytical model for dimensioning transport bandwidths in the Long Term Evolution (LTE) access network. In this work the criterion for dimensioning is the transport network delay QoS (at the packet level). The presented analytical model takes into considerations the key features of the LTE radio interface and the use of Differentiated Service (DiffServ) QoS scheme in the LTE access transport network. Furthermore, the proposed dimensioning approach can be performed for a single transport link as well as for the entire transport network. For validating the analytical dimensioning models, a developed LTE system simulation model is used. The presented results demonstrate that the proposed analytical models can appropriately estimate the transport network delays for different QoS priorities and hence can be used for bandwidth dimensioning for various traffic and network scenarios.