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Read the number, not just the stars
The ISEER rating on the BEE star label measures an AC's cooling per unit of electricity across Indian temperatures from 24 to 43 °C, and it is a better way to compare two ACs than the star count alone.
From The AC in Your Flat. Updated 4 November 2026.
The Bureau of Energy Efficiency's label carries a star band, an ISEER figure, an estimate of units per year and a validity period. Stars move as the rules tighten, so a star count only makes sense with its date.
What does ISEER mean?
ISEER stands for Indian Seasonal Energy Efficiency Ratio. The Ministry of Power's 2016 release says it's a weighted average of performance at outside temperatures between 24 and 43 °C, based on Indian weather data. The older test used a single condition. Down To Earth's 2025 piece says the label's yearly figure assumes about 1,600 hours of cooling. Compare models on that basis, and scale it to your own use.
From the Ministry of Power's May 2023 table. The earliest periods used the older test, so the rise is partly a change of method.
What changed in January 2026?
The stars got harder to earn, but the exact 2026 table is hard to pin down from here. Onida, a maker, says thresholds for each band rose 10 to 14 per cent on 1 January 2026, and that a model rated 5-star under the 2025 rule now counts as 4-star, with no change to how it performs. Figures for the new 5-star cut-off differ across retailer and maker sites. We could not open the Bureau's own label site from where we work, so we leave that number out. Look at the ISEER figure and the validity dates on the actual label in the shop.
Averages for 3-star, 4-star and 5-star ACs from the Centre for Science and Environment, reported by Down To Earth in September 2025. These predate the 2026 change. Units are kWh per year.
Is 5-star worth the extra money?
Sometimes. Down To Earth reports yearly savings of about ₹1,200 to ₹1,800 for 5-star over 3-star, at ₹4.5 to ₹6.65 per unit, and a median price gap of ₹7,000 for 1.5-ton models in a 2024 Prayas survey, so a payback of 4 to 6 years. Those figures are from 2024–25, and your tariff and hours may differ. If you run the AC most of the year, the case is better; for a few weeks a year, it's weaker.
What to do
Yours to do
- Read the ISEER, the units per year and the validity dates on the label itself.
- Compare two models of the same capacity at the same label period.
- Work out your own hours and tariff before paying more for stars.
Leave to the trained person
- The fitting. A good label can't save a badly placed outdoor unit.
Also asked
Does my old 5-star AC become worse in 2026?
No. Onida says the rating band changes, not the AC.
Are window ACs rated the same way?
They are on the same programme, on a lower scale. The 2020 notification gave 2.70 to 3.50 for window units and 3.30 to 5.00 for split units, for the period starting in January 2021.
Where this came from
- Press Information Bureau, 24 August 2016: What ISEER measures
- Press Information Bureau, 10 May 2023: Star-band table to December 2024
- Press Information Bureau, 6 January 2020: Scale from January 2021
- Down To Earth, 22 September 2025: Label contents, average units, costs, payback
- Onida, 2026 BEE standards: Maker's account of the 2026 change
This story rests on those pages, opened or checked by 4 November 2026, and on no tests of our own. Maker pages speak for their makers, and rules and wiring differ by building, so check your own manual.