Antarctic sea ice plays a crucial role in the global climate system and sea ice in the polar regions are sensitive indicators of short and long-term climate change. The onset of the instrumental era has enabled large-scale study and observation of sea ice, but the short duration of this satellite period hinders understanding of long term behavioural trends in Antarctic sea ice. Paleo reconstructions of sea ice from ice cores offers a solution to this. It has been previously demonstrated that sodium from sea salts has potential as a proxy for larger changes in sea ice extent over glacial to interglacial timescales. This study focuses on establishing chloride, a stable sea salt, as a viable and robust sea ice proxy in the Southern Ocean. The reconstruction of sea ice from ice cores was reviewed by Abram et. al (2013) and sea salts were considered a potential proxy. Mayekar et al (2019) identified key factors that are known to influence sea ice reconstructions from ice cores: (i) chemical species used and (ii) their seasonality, (iii) modes of climate variability, (iv) spatial and (v) temporal variation (vi) sea ice regions to reconstruct sea ice for the past 100 years and thus identified chloride as a robust proxy for reconstructing Antarctic sea using ice-cores from 3 separate sites in East Antarctica: Mount Brown South, Aurora Basin North and Dome Summit South. We show that chloride has a significant relationship with sea ice at these sites highlighting a climate signal that can help reconstruct sea ice over the last two millennia and potentially through the Holocene.