Voltage level shifter (VLS) circuits employing a pre-conditioning circuit for pre-conditioning an input signal to be voltage level shifted in response to a pre-charge phase are disclosed. A VLS circuit is configured to voltage level shift an input signal in a lower voltage domain on an output node in a higher voltage domain. The VLS circuit includes a pre-charge circuit configured to pre-charge the output node in a pre-charge phase. The VLS circuit also includes a pull-up circuit and a pull-down circuit that are configured to pull-up and pull-down the pre-charge phase of the output node, respectively, in an evaluation phase based on a logic state of the input signal to generate the output signal. To mitigate or avoid contention between the pull-up and pull-down circuits in the evaluation phase, the input signal is pre-conditioned such that the pull-down circuit is deactivated in response to the pre-charge phase.