Concrete’s low tensile strength makes it prone to cracks due to shrinkage or loading, creating entry points for harmful agents such as chlorides, sulphates or carbon dioxide, leading to concrete deterioration and reinforcement corrosion. To enhance durability, improved concrete mixes are necessary. This study investigates a recently patented, in-house developed, silver-incorporated, alginate-based, superabsorbent polymer (Ag-SAP) as a multifunctional admixture. Similar to commercially available superabsorbent polymers (SAPs), Ag-SAPs provide internal curing to mitigate shrinkage and improve freeze-thaw resistance. Furthermore, the incorporation of silver ions enables Ag-SAPs to bind chlorides, reducing the risk of chloride-induced corrosion. The silver incorporation decreases the swelling capacity, thereby limiting strength reduction in mortar or concrete. However, when the silver ions bind to chlorides, the swelling capacity increases, promoting crack sealing and healing. First of all, the chloride binding and swelling capacity of the Ag-SAPs was determined and compared to the swelling capacity of commercial SAPs. Then, 3 mortar mixes (w/c ratio 0.5) were made: one with 0.32 m% Ag-SAPs, one with 0.32 m% commercial SAPs, and a reference mix. Each mixture’s flexural and compressive strength, air void content and shrinkage behaviour were investigated. Results showed commercial SAPs exhibited higher absorption in demineralized water and cement filtrate compared to Ag-SAPs, increasing air void content and reducing compressive strength. Their higher swelling capacity provided a higher autogenous shrinkage reduction compared to Ag-SAPs, though neither fully mitigated shrinkage. Overall, results indicate that Ag-SAPs have potential, but further research is needed to determine the chloride binding capacity inside a cementitious matrix.