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Concrete accounts for approximately 7% of global anthropogenic CO emissions, nearly two-thirds of which are hard-to-abate limestone calcination emissions that are partially offset through natural carbonation. This study presents a dynamic cradle-to-grave carbon footprint assessment of six scenarios for hollow concrete blocks, evaluating carbon capture, carbonation curing and mineral carbonation alongside their impact on natural CO uptake. Natural carbonation offsets – of calcination emissions, rising to –, depending on modelling assumptions, with carbonation curing. Static accounting overestimates this benefit by –. Compared with conventional concrete, carbon capture, utilization, and storage scenarios can reduce emissions by –, with carbon capture responsible for – and the elimination of steam curing for –. Subsequent carbonation curing and mineral carbonation components themselves yield only marginal emission savings of –, but reduce the reliance on geological CO storage by – relative to a capture-only scenario. These findings show that carbon capture and eliminating steam curing drive the emission reductions, while carbonation curing and mineral carbonation offer alternatives to CO storage.