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<p>Tropospheric ozone is important to future air quality and climate. We investigate ozone changes and ozone sensitivity to changing emissions in the context of climate change from the present day (2004–2014) to the future (2045–2055) under a range of shared socio-economic pathways (SSPs). We apply the United Kingdom Earth System Model, UKESM1, with an extended chemistry scheme including more reactive volatile organic compounds (VOCs) to quantify ozone burdens as well as ozone sensitivities globally and regionally based on nitrogen oxide (<span class="inline-formula">NO_<i>x</i></span>) and VOC mixing ratios. We show that the tropospheric ozone burden increases by 4 % under a development pathway with higher <span class="inline-formula">NO_<i>x</i></span> and VOC emissions (SSP3-7.0) but decreases by 7 % under the same pathway if <span class="inline-formula">NO_<i>x</i></span> and VOC emissions are reduced (SSP3-7.0-lowNTCF) and by 5 % if atmospheric methane (<span class="inline-formula">CH₄</span>) mixing ratios are reduced (SSP3-7.0-lowCH4). Global mean surface ozone mixing ratios are reduced by 3–5 ppb under SSP3-7.0-lowNTCF and by 2–3 ppb under SSP3-7.0-lowCH4. However, surface ozone changes vary substantially by season in high-emission regions under future pathways, with decreased ozone mixing ratios in summer and increased ozone mixing ratios in winter when <span class="inline-formula">NO_<i>x</i></span> emissions are reduced. VOC-limited areas are more extensive in winter (7 %) than in summer (3 %) across the globe. North America, Europe, and East Asia are the dominant VOC-limited regions in the present day, but North America and Europe become more <span class="inline-formula">NO_<i>x</i></span>-limited in the future mainly due to reductions in <span class="inline-formula">NO_<i>x</i></span> emissions. The impacts of VOC emissions on ozone sensitivity are limited in North America and Europe because reduced anthropogenic VOC emissions are partly offset by higher biogenic VOC emissions. Ozone sensitivity is not greatly influenced by changing <span class="inline-formula">CH₄</span> mixing ratios. South Asia becomes the dominant VOC-limited region under future pathways. We highlight that reductions in <span class="inline-formula">NO_<i>x</i></span> emissions are required to transform ozone production from VOC to <span class="inline-formula">NO_<i>x</i></span> limitation, but that these lead to increased ozone mixing ratios in high-emission regions, and hence emission controls on VOC and <span class="inline-formula">CH₄</span> are also necessary.</p>