<jats:title>Abstract</jats:title><jats:p>Global CO<jats:sub>2</jats:sub>level presently recorded at 400 ppm is expected to reach 550 ppm in 2050, an increment likely to impact plant growth and productivity. Using targeted LC-MS and GC-MS platforms we quantified 229 and 29 metabolites, respectively in a time-course study to reveal short-term responses to different concentrations (1, 3, and 10 mM) of bicarbonate (HCO<jats:sub>3</jats:sub><jats:sup>−</jats:sup>) under light and dark conditions. Results indicate that HCO<jats:sub>3</jats:sub><jats:sup>−</jats:sup>treatment responsive metabolomic changes depend on the HCO<jats:sub>3</jats:sub><jats:sup>−</jats:sup>concentration, time of treatment, and light/dark. Interestingly, 3 mM HCO<jats:sub>3</jats:sub><jats:sup>−</jats:sup>concentration treatment induced more significantly changed metabolites than either lower or higher concentrations used. Flavonoid biosynthesis and glutathione metabolism were common to both light and dark-mediated responses in addition to showing concentration-dependent changes. Our metabolomics results provide insights into short-term plant cellular responses to elevated HCO<jats:sub>3</jats:sub><jats:sup>−</jats:sup>concentrations as a result of ambient increases in CO<jats:sub>2</jats:sub>under light and dark.