Free tool · Carbon Tax Phase 2

Carbon tax calculator. Honest edition.

Most carbon tax calculators multiply your electricity by the headline rate and hand you a scary number. The law does not work that way. This one shows your real 2026 position: what you owe, what you are shielded from, and where the exposure actually sits.

Your annual consumption

Offices, retail, mixed-use and logistics. Direct liability rules differ for large emitters; switch profiles if you run major coal or gas plant.

kWh / year

A 10 000 m² office typically uses 1.5–2.5 million kWh a year.

litres / year
More fuels and settings
litres / year
kg / year
GJ / year
R / kWh

Used only for the savings scenario, not for tax.

Carbon price exposure · 2026

R 0

Your total footprint valued at the full 2026 rate of R 308/tCO2e, before allowances and shields. This is the number that belongs in your board pack, not your tax return.

A measured 25% electricity reduction on these numbers is worth R 0 a year in energy costs and Section 12L deductions. That is the number worth acting on.

How 12L works
Show the workings: rates, factors and sources

Every constant below is from enacted law or official publications, verified July 2026. This calculator estimates; a SANEDI-registered assessment and metered baseline turn estimates into claimable numbers.

ConstantValueSource
Carbon tax rate 2026 (Phase 2)R 308/tCO2eBudget 2026; TLAA 2025
Trajectory 2027–2030R 347 / 385 / 424 / 462TLAA 2022; Treasury Phase 2 paper
Grid electricity factor (incl. losses)0.99 kgCO2e/kWhDFFE 2023 Grid Emission Factors Report
Diesel2.69 kgCO2e/lDFFE methodology (Kornelius et al. 2022)
Petrol2.30 kgCO2e/lDFFE methodology
LPG3.00 kgCO2e/kgDFFE methodology
Natural gas55.66 kgCO2/GJCarbon Tax Act Sch 1 (2026)
Coal (other bituminous)≈2.20 tCO2/tCarbon Tax Act Sch 1 (2026)
Carbon fuel levy (from 1 Apr 2026)diesel 23c/l · petrol 19c/lBudget 2026
Commercial liability threshold25 000 tCO2e/yrBudget 2026 (proposed, legislation pending)
Electricity price neutralityto 31 Dec 2030TLAA 2025; NERSA
Section 12L deduction95c/kWh verified savingsIncome Tax Act s12L

Caveats: the 25 000 tCO2e commercial threshold was announced in Budget 2026 and awaits enactment; the R 640/t punitive rate above carbon budgets is enacted but not yet in force; offset allowances require purchased credits (recent SA prices R 120–R 200/t); Scope 2 is reported here with transmission and distribution losses included, and the post-2030 electricity figure is a scenario, not a tax.

Get this as a board-ready report

We will email your results as a one-page PDF with the assumptions cited, your 2026–2030 cost curve, and the three highest-value moves for your portfolio.

FAQ

Carbon tax questions, answered properly

What is the South African carbon tax rate in 2026?

R 308 per tonne of CO2e, effective 1 January 2026, the first year of Phase 2 and a 30.5% increase on the 2025 rate of R 236. The legislated trajectory continues to R 347 in 2027, R 385 in 2028, R 424 in 2029 and R 462 in 2030.

Is my office building directly liable for carbon tax?

Almost certainly not. Budget 2026 announced that for commercial and institutional buildings the 10 MW thermal capacity threshold is replaced by a 25,000 tCO2e annual emissions threshold, effective 1 January 2026 (legislation pending). That is roughly 9.3 million litres of diesel a year, far beyond any normal backup generator fleet. Diesel and petrol already carry carbon tax in the pump price, so there is nothing to file for those litres either.

Does Eskom pass the carbon tax through in my electricity tariff?

Not before 2031. Electricity price neutrality has been extended to 31 December 2030: the old 3.5c/kWh generation levy was scrapped on 1 January 2026, the carbon tax replaces it rand-for-rand, and NERSA has disallowed recovery of carbon tax through tariffs. From 2031 that commitment lapses, which is why the calculator shows a post-2030 scenario.

How do the tax-free allowances work in Phase 2?

The basic 60% allowance is retained until 2030. Trade-exposed sectors can add up to 10%, the performance allowance adds up to 5%, and the carbon offset allowance rises to 15% for combustion emissions. The 5% carbon budget allowance fell away on 1 January 2026. The realistic maximum for combustion emissions is 90%, which puts the effective 2026 rate between R 30.80 and R 123.20 per tonne depending on your profile.

If my liability is near zero, why does the footprint number matter?

Because everyone else prices it even when SARS does not. GRESB, CDP, JSE disclosure and lender due diligence all ask for your footprint; EU CBAM reaches exporters through supply chains; and from 2031 the electricity shield can lapse while the rate keeps climbing. The footprint you measure today is the liability curve you manage tomorrow.

How does Section 12L interact with carbon tax?

Section 12L pays you for measured, verified energy savings at 95 cents per kWh as a tax deduction. Cutting consumption reduces your carbon footprint and your future carbon cost curve while generating a claimable deduction today. It is the cash-positive side of the same measurement work.

Estimates start conversations. Baselines win claims.

A metered baseline turns this estimate into a defensible footprint for GRESB and JSE disclosure, and into verified savings SARS will accept for Section 12L.

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