The Arctic flora occupies a narrow zone between the natural tree line and the Arctic Ocean, and is highly sensitive to changes in global climate. In recent decades, this region has been warming at rates 3–4 times the global average, a phenomenon known as Arctic amplification. This rapid warming will cause permafrost thaw and methane release and alter atmospheric and oceanic circulation. By the end of the 21st century, the mean surface temperature over the Arctic could be ∼2.8°C–10.4°C warmer than now depending on which greenhouse gas (GHG) emission scenarios play out (from SSP1-2.6 to SSP5-8.5). The magnitude and rate of this projected future climate change are unparalleled in the past several million years, underscoring the urgency of predicting potential changes in the Arctic flora under different emission scenarios. Climate change will cause species to shift, contract and/or expand their ranges, and consequently alter community composition, species richness patterns and thus ecosystem functioning. The Arctic flora is home to 2041 vascular plant species that are tolerant of low temperatures, frozen soils, desiccation and short reproductive windows (Fig. S1). To date, only small-scale species modelling limited to relatively few taxa has been conducted, which precludes broad understanding of the details and magnitude of that change, and responses of the Arctic flora as a whole.