The traceability for thermal voltage converters (TVCs) usually depends on a range-to-range buildup technique that requires either very small voltage-level dependencies of the converters or precise knowledge of these level dependencies. In practice, this inevitably leads to uncertainties that accumulate in the buildup process and dominate the overall uncertainty of the high-voltage ac-dc transfer measurement. This paper presents an alternative technique that uses a 1000-V inductive voltage divider (IVD) developed at the national measurement institute, linfield, Australia (NMIA). The use of the IVD eliminates the need for the buildup, which leads to a significant reduction in the uncertainty. The standard uncertainty of the new high-voltage TVC calibration setup is on the order of 1 muV/V, which is significantly smaller than the uncertainties derived from the buildup technique.