The Green Blind Spot 113 companies · measured 2026-10-02

Media and telecoms · rank 73 of 113

2.14grams of CO2 per visit

BT's website emits 2.14 g of CO2 per visit, 6.0× the worst passing grade.

That is 0.37 g above the cohort median of 1.78 g, and puts the site in the heavier half of the 113 companies ranked this edition.

Grade F on the Sustainable Web Design scale. How grades A+ to F are set.

The numbers behind it

3 of 3in Media and telecoms
6.5 MBmedian page weight
169.5 tCO2 a year from the pages measured
28 pagesmeasured, covering 92% of traffic
Fgrade, unadjusted scale

Annual figures cover the 28 pages I measured and estimated organic search traffic only, so the real total is higher. Coverage is published so you can judge how representative the number is.

One visit ≈ a 10-watt LED bulb for 26 minutes. A year of estimated search visits to the pages measured ≈ driving a new car 1.8 million km, or the electricity of 140 Dutch homes. What these numbers mean

Where this site sits in the cohort

rank 1 · 0.11 grank 113 · 7.60 g

Grades A+ to E: up to 0.36 g. 2 companies here.

  1. A+up to 0.040 g0 companies
  2. Aup to 0.079 g0 companies
  3. Bup to 0.145 g1 company
  4. Cup to 0.209 g0 companies
  5. Dup to 0.278 g1 company
  6. Eup to 0.359 g0 companies
  7. Fabove 0.359 g111 companies

BT is the dark bar. The band along the bottom is every passing grade, A+ to E.

Against the other media and telecoms companies

The Guardianrank 3 overall · lightest 25% 0.48 g
Telefonicarank 20 overall · lightest 25% 0.94 g
BTrank 73 overall · heavier half 2.14 g

Bars share one scale within the sector, lightest first. See all media and telecoms companies.

Why this company is in the index

Listed because: SBTi net-zero 2041 validated.

Claims: Validated science-based climate target

Inclusion is based on a company's own public claims, never on whether it is a client of mine. How this is measured.

Work at BT? I can show you which pages carry the weight and what it would take to cut it.

Ask what drives this number · Tell me if this looks wrong

Cite this: The Green Blind Spot, 2026-Q4 edition, Baba SEO. https://greenblindspot.com/2026-q4/company/bt-com/