This study examines the carbon footprints (CFs) of Spanish household food consumption in 2022, based on survey-based data. The results are assessed considering differences in food consumption patterns across socioeconomic status (SES), categorised by their job status and level of education into high and middle-high, middle, middle-low, and low SES. The analysis included weight, energy, and nitrogen intake and used Life Cycle Assessment (LCA) to assess greenhouse gas (GHG) emissions in terms of carbon dioxide equivalent (CO2eq). Observed patterns are compared to three reference diets, i.e., the Mediterranean diet (MD), the Planetary healthy diet (PHD), and the Spanish Guideline (SG), selected for their health benefits, low environmental impacts, and cultural relevance. The results revealed overconsumption of ultra-processed foods (UPF) in the average diet, especially processed pork meat, and underconsumption of vegetables and pulses, compared to the reference diets. This overconsumption was higher for high SES, while underconsumption was more evident in lower SES. As a result, high SES show average CFs that are 24% higher than those of low SES, ranging from 2.05 to 2.69 kgCO2eq/person/day. Compared with the reference diets, the average Spanish household consumption showed a CF 29% higher. Shifting towards healthier and low-carbon diets would require reducing UPFs consumption per capita while increasing the consumption of vegetables, pulses, and plant-based products. The study highlights the importance of including a socioeconomic perspective to tackle the debate on agri-food transition with different target group policies.