As the first intrinsic antiferromagnetic topological insulator, ${\mathrm{MnBi}}_2{\mathrm{Te}}_4$ offers a platform for investigating topological phenomena driven by magnetism. Prior studies focused on bulk single crystals and exfoliated flakes, but the extreme two-dimensional (2D) limit remains underexplored, despite theoretical predictions of exotic behavior. In particular, synthesis and atomic-scale characterization of ultrathin ${\mathrm{MnBi}}_2{\mathrm{Te}}_4$ films remain challenging. Here we explore molecular beam epitaxy grown ${\mathrm{MnBi}}_2{\mathrm{Te}}_4$ thin films down to a single-layer thickness. Structural characterization via electron and x-ray diffraction, atomic force microscopy, and scanning tunneling microscopy confirms layer-by-layer growth and high crystallinity, while magnetotransport measurements show the expected magnetic signatures. Interestingly, scanning tunneling microscopy and quasiparticle interference imaging reveal Dirac-like surface states that persist even in monolayer films and monolayer islands. Our experiments provide elusive atomic-scale insights into the band structure of ${\mathrm{MnBi}}_2{\mathrm{Te}}_4$ in the 2D limit and under lateral confinement, and establish a foundation for the synthesis of heterostructures based on monolayer ${\mathrm{MnBi}}_2{\mathrm{Te}}_4$ and device applications.

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• Density of states
• Magnetic systems
• Monolayer films
• Topological materials
• Scanning tunneling microscopy
• Scanning tunneling spectroscopy