The relay of information at the retinogeniculate synapse, the connection between retina and visual thalamus, begins days before eye opening, and is thought to play an important role in the maturation of neural circuits in the thalamus and visual cortex. Remarkably, during this period of development, the retinogeniculate synapse is immature, with single retinal ganglion cell inputs evoking an average peak excitatory postsynaptic current (EPSC) of only ~40 pA when compared to 800 pA in mature synapses. Yet, at the mature synapse, EPSCs greater than 400 pA are needed to drive relay neuron firing. This raises the question of how small amplitude EPSCs can drive transmission at the immature retinogeniculate synapse. Here we find that several features of the immature synapse, when compared to the mature synapse, contribute to synaptic transmission. First, although the peak amplitude of EPSC is small, the decay time course of both AMPA and NMDA receptor (NMDAR) currents is significantly slower. The prolonged time course of NMDAR currents is a result of the presence of NR2B as well as NR2C/D subunits. In addition, extended presence of neurotransmitter released prolongs the synaptic current time course. Second, reduced sensitivity to magnesium block results in significantly greater synaptic charge transfer through NMDAR. Third, AMPAR currents contribute to the spike latency, but not to temporal precision at the immature synapse. Furthermore, intrinsic excitability is greater. These properties enable immature synapses with predominantly NMDAR and little or no AMPAR to contribute to the relay of information from retina to visual cortex.