mˈækɪnən wʌz bˈɔːɹn ɪn ˈɛʃɚ, sˈʌɹi ænd wʌz ˈɛdʒuːkˌeɪɾᵻd æɾ ˈiːtən kˈɑːlɪdʒ, bᵻfˌoːɹ stˈʌdiɪŋ dɹˈɑːmə æt ðə jˌuːnɪvˈɜːsᵻɾi ʌv mˈæntʃɛstɚ.
Mackinnon was born in Esher, Surrey and was educated at Eton College, before studying drama at The University of Manchester.