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<p>We report a 40-year history of SF<span class="inline-formula">₆</span> atmospheric mole fractions measured at the Advanced Global Atmospheric Gases Experiment (AGAGE) monitoring sites, combined with archived air samples, to determine emission estimates from 1978 to 2018. Previously we reported a global emission rate of <span class="inline-formula">7.3±0.6</span>&thinsp;Gg&thinsp;yr<span class="inline-formula">⁻¹</span> in 2008 and over the past decade emissions have continued to increase by about 24&thinsp;% to <span class="inline-formula">9.04±0.35</span>&thinsp;Gg&thinsp;yr<span class="inline-formula">⁻¹</span> in 2018. We show that changing patterns in SF<span class="inline-formula">₆</span> consumption from developed (Kyoto Protocol Annex-1) to developing countries (non-Annex-1) and the rapid global expansion of the electric power industry, mainly in Asia, have increased the demand for SF<span class="inline-formula">₆</span>-insulated switchgear, circuit breakers, and transformers. The large bank of SF<span class="inline-formula">₆</span> sequestered in this electrical equipment provides a substantial source of emissions from maintenance, replacement, and continuous leakage. Other emissive sources of SF<span class="inline-formula">₆</span> occur from the magnesium, aluminium, and electronics industries as well as more minor industrial applications. More recently, reported emissions, including those from electrical equipment and metal industries, primarily in the Annex-1 countries, have declined steadily through substitution of alternative blanketing gases and technological improvements in less emissive equipment and more efficient industrial practices. Nevertheless, there are still demands for SF<span class="inline-formula">₆</span> in Annex-1 countries due to economic growth, as well as continuing emissions from older equipment and additional emissions from newly installed SF<span class="inline-formula">₆</span>-insulated electrical equipment, although at low emission rates. In addition, in the non-Annex-1 countries, SF<span class="inline-formula">₆</span> emissions have increased due to an expansion<span id="page7272"/> in the growth of the electrical power, metal, and electronics industries to support their continuing development.</p> <p>There is an annual difference of 2.5–5&thinsp;Gg&thinsp;yr<span class="inline-formula">⁻¹</span> (1990–2018) between our modelled top-down emissions and the UNFCCC-reported bottom-up emissions (United Nations Framework Convention on Climate Change), which we attempt to reconcile through analysis of the potential contribution of emissions from the various industrial applications which use SF<span class="inline-formula">₆</span>. We also investigate regional emissions in East Asia (China, S. Korea) and western Europe and their respective contributions to the global atmospheric SF<span class="inline-formula">₆</span> inventory. On an average annual basis, our estimated emissions from the whole of China are approximately 10 times greater than emissions from western Europe. In 2018, our modelled Chinese and western European emissions accounted for <span class="inline-formula">∼36</span>&thinsp;% and 3.1&thinsp;%, respectively, of our global SF<span class="inline-formula">₆</span> emissions estimate.</p>