The growing volume of waste materials poses significant environmental challenges, while CO2 emissions from cement production contribute to global warming. This study explores the potential of using incineration ashes, in particular fly ash (FA) and bottom ash (BA), in construction materials, both to reduce landfill waste and to capture CO2 through carbonation curing. While bottom ash has been used in construction (limited to low grade applications), most fly ash is landfilled. By incorporating bottom ash into carbonation curing, CO2 can be captured during the curing process, providing environmental and economic benefits. This research investigates the carbon sequestration capacity of bottom ashes as well as fly ashes of municipal solid waste incinerator (MSWI) and co-combustion (CC) ashes under accelerated carbonation conditions. Using techniques such as XRF, TGA and mass uptake analysis, the results show that finer particles and higher CO2 curing concentrations improve carbonation efficiency. From the tested materials these results also highlight optimal carbonation conditions and suggest a strategy for the use of incineration ash in carbon curing concrete, providing guidance for sustainable construction applications. MSWI FA, as studied in this work, showed the highest sequestration potential.