Manufacturing and transport account for about 79 kgCO2e of a smartphone's total footprint of 80 kgCO2e over 2 and a half years of use, according to Impact CO2, ADEME's website. Electricity for charging accounts for less than 1 kgCO2e over that period. Keeping the phone for 4 and a half years brings its footprint down from 32 to 18 kgCO2e a year (our calculation).
Read the source article: Digital carbon footprint statistics for 2026, with sources