The biological capture of carbon dioxide (CO2) by biosequestration is a central mechanism for reducing atmospheric CO2 concentrations. As Australia seeks to capitalise on biosequestration opportunities, interest is growing in restoring inland wetlands, which may be important carbon sinks, for offset purposes. Wetlands have often undergone widespread alteration via agricultural and urban development, and water extraction and degradation of wetland soils can trigger the release of ancient, stored carbon into the atmosphere, turning them into carbon sources. We investigated whether rehabilitating wetlands can restore carbon stocks and sequestration capacity in the central Murray region, NSW. We applied a ‘space-for-time’ analysis, capitalising on the region’s 20-year legacy of wetland rehabilitation. For 12 wetlands, soil core samples were analysed (n = 90) for elemental carbon to quantify carbon stocks, and 210Pb age-dated to determine carbon accretion rates. Wetland carbon stocks increased linearly with time since rehabilitation. Importantly, this relationship existed despite carbon stocks also being influenced by other factors that could not be controlled, which had been expected to limit the detectability of carbon gains (e.g. land-use prior to rehabilitation, soil type, frequency of water inundation and elevation). Land-use prior to rehabilitation explained significant variation, with wetlands that were previously both cropped and grazed having higher carbon stocks than wetlands that were previously subject to grazing only. Carbon stocks in rehabilitated wetlands were similar (87 Mg Corg ha-1) if not higher than those reported for other freshwater wetlands in Australia, suggesting that carbon sequestration capacity can be restored within reasonable (5 – 20 yr) time frames. Based upon preliminary data on soil accretion rates, estimated carbon sequestration rates at the sites studied are between 1.0 and 4.1 Mg CO2e ha-1 yr-1. Our study provides promising experimental evidence that wetland rehabilitation can help restore the carbon sequestration capacity of wetlands.