  We predict the number of black holes with stellar companions that are
potentially detectable with Gaia astrometry over the course of its five-year
mission. Our model estimates that nearly 2$\times$10$^5$ astrometric binaries
hosting black holes and stellar companions brighter than Gaia's detection
threshold, G $\sim$ 20, should be discovered with 5$\sigma$ sensitivity. Among
these detectable binaries, systems with longer orbital periods are favored, and
black hole and stellar companion masses in the range M$_{BH} \sim$ 6-10
M$_\odot$ and M$_* \sim$ 1-2 M$_\odot$, respectively, are expected to dominate.
