The described techniques relate to methods, systems, devices, and apparatuses that support narrowband reference signal (NRS) configuration for non-anchor carriers. Generally, the described techniques provide for increasing the length of an NRS scrambling sequence for non-anchor carriers. For example, the NRS scrambling sequence initialization equation may be a function of system frame number. A base station may transmit to a user equipment (UE) a non-anchor carrier configuration indicating that the NRS scrambling sequence is extended with respect to other NRS scrambling sequences. For example, the non-anchor carrier configuration may indicate the scrambling sequence initialization for the NRS. In some examples, the length of the NRS scrambling sequence is increased by extending the number of possible initializations. The base station and UE may communicate based on the extended length of the NRS scrambling sequence for non-anchor carriers of the NRS.