Cities are a major source of carbon emissions and should play an important role in reducing carbon emissions. This study applies the method of multi-scale input–output analysis (MSIO) to analyze the consumption-based carbon emissions of Tianjin in 2012. This method can estimate the carbon emissions embodied in imported products. The results reveal that the production-based carbon emissions of Tianjin were 1.52 × 108 tonnes CO2 in 2012, which had increased over 50% since 2007. Meanwhile, the consumption-based carbon emissions of Tianjin city were 2.55 × 108 tonnes CO2, 1.71 times higher than those in 2007 and 1.67 times the amount of production-based carbon emissions in 2012. Regarding the total embodied carbon emissions involved in the Tianjin economy in 2012, about 6% were from foreign countries, over 60% were from other regions of China, and only one-third were territorial-based or production-based carbon emissions. Correspondingly, Tianjin respectively exported 11% and 34% of the total embodied carbon emissions to foreign countries and other regions in China, while over half were embodied in the local final demand. Tianjin was a carbon budget importer in domestic trade and an exporter in international trade in both 2007 and 2012. However, when both domestic and international trades are considered, Tianjin had shifted from a carbon budget exporter in 2007 to an importer in 2012. Since 2007, the carbon nexus between Tianjin and other regions in China had become much closer (carbon emissions embodied in domestic trade increased 103.47%), but the connection with foreign countries became looser (carbon emissions embodied in international trade decreased 21.96%). Compared to Beijing in 2012, it is evident that there were less carbon emission transfer issues for Tianjin city.