If you've recently bought a light bulb and found yourself staring at a label showing an F or even G energy rating, you'd be forgiven for assuming you've bought something wildly inefficient. You haven't. In September 2021, the EU and UK introduced a completely rescaled energy labelling system for lighting products — and overnight, bulbs that had been rated A++ became E or F under the new rules. Not because they got worse. Because the rules got stricter.
This guide cuts through the confusion. We explain exactly what changed, how to read the new labels correctly, what it means for the bulbs you're buying today, and how to find the most genuinely efficient LED light bulbs for your home or business.
Why the energy labels changed in 2021
The original EU energy label — introduced in the 1990s — used a scale running from A (most efficient) down to G (least efficient). Over time, as technology improved, manufacturers kept hitting the top of the scale. Extra categories were added: first A+, then A++, then A+++. By 2020, the scale had become so top-heavy that almost every modern LED bulb was rated A++ or A+++, making the label essentially useless for comparing products.
By 2021, the old label had lost its purpose — almost every LED was rated A++ or A+++, giving consumers no useful way to compare. The rescaling was designed to fix that.
The European Commission responded by scrapping the plus categories entirely and resetting the scale to a clean A–G system under Regulation (EU) 2019/2015, which came into force on 1 September 2021. The same regulation was adopted into UK law under The Ecodesign for Energy-Related Products and Energy Information (Lighting Products) Regulations 2021. The thresholds were deliberately raised to leave room for the next generation of lighting technology — making A and B ratings aspirational targets rather than easily achieved benchmarks.
Old scale vs new scale — side by side
The product hasn't changed. The efficiency hasn't changed. Only the letter has changed. Here's how the two scales compare for LED bulbs:
| Old Rating (pre-2021) | New Rating (from 2021) | Efficiency (lm/W) | Typical bulb type |
|---|---|---|---|
| ≥ 120 lm/W | Standard LED GLS | ||
| ≥ 100 lm/W | Most modern LED bulbs | ||
| ≥ 85 lm/W | Standard LED candles, GU10s | ||
| ≥ 50 lm/W | Older or decorative LEDs | ||
| < 50 lm/W | Halogen, incandescent |
Under the new system, A and B ratings are currently nearly empty — reserved for technologies not yet in mainstream production. The top of today's LED market sits comfortably at C, D and E. An F-rated LED under the new system is still enormously more efficient than any halogen or incandescent bulb ever was.
How to read the new energy label
Every new label follows a standardised format. Here's what each element tells you:
Supplier & Model
The manufacturer's name and the specific model number. Useful for cross-referencing with the EPREL database.
A–G Scale
The coloured bar from dark green (A) to red (G) with an arrow showing where this product sits on the new rescaled system.
kWh/1000h
Energy consumption per 1,000 hours of use. This is the most practical number — use it to calculate running costs directly.
QR Code
New to the 2021 label. Scans directly to the EU's EPREL product database where you can verify the full technical specification sheet.
The most useful number on the label
Forget the letter for a moment. The kWh/1000h figure tells you exactly how much electricity this bulb will use over 1,000 hours. A bulb rated 8 kWh/1000h will cost roughly £1.60 to run for 1,000 hours at today's average UK electricity rate of around 20p/kWh. That's the number to compare when choosing between products.
Why has my efficient bulb dropped to F or G?
This is the question we hear most often — and it causes genuine alarm. Someone buys an Osram or Integral LED bulb that was previously rated A++, and finds the new packaging shows an F rating. Nothing has changed about the bulb itself. It produces the same amount of light. It consumes the same amount of electricity. It will last just as long.
What changed is the measuring stick. The new efficiency thresholds were deliberately set far above what current mainstream technology can achieve at scale. An LED bulb needs to produce more than 210 lumens per watt to achieve an A rating under the new system — a threshold that only specialist laboratory-grade components can currently approach. The vast majority of commercially available LED GLS bulbs, LED candle bulbs and GU10 spotlights fall between E and G under the new scale — and that is entirely expected and correct.
An F-rated LED bulb under the new 2021 system still uses up to 85% less energy than the incandescent it replaced. The letter changed. The efficiency did not.
What is an LED Class A bulb?
A true LED Class A rating under the new 2021 system means the bulb achieves an energy efficiency index (EEI) placing it in the top band of the rescaled A–G system. In practice, these are high-specification bulbs engineered with the most advanced LED chips and driver electronics available, typically producing 150 lm/W or above with exceptional consistency and longevity.
New 2021 energy label — A to G scale
At Light Shop Direct we stock a growing range of A-class LED light bulbs achieving the new top-band rating. These are available in BC (B22) and ES (E27) fittings and represent the most energy-efficient bulbs commercially available today in standard domestic formats.
The real cost savings of upgrading to LED
Whatever their letter rating under the new system, modern LED bulbs remain dramatically more efficient than the halogen and incandescent technology they replace. Here's what the numbers actually look like:
For commercial and industrial users, the savings are even more significant. Replacing traditional discharge lamps with LED corn lamps in high-bay or street lighting applications typically cuts energy consumption by 60–70% and eliminates the maintenance cost of frequent lamp replacements. Our LED batten lights and highbay LED lights are designed specifically for these retrofit applications.
What should I actually buy?
Here's the practical guidance. Stop focusing on the letter and focus on two things instead: lumens (brightness) and kWh/1000h (running cost). A higher lumen output at a lower kWh figure is what you're looking for, regardless of the letter assigned.
Quick buying guide by fitting type
- LED GLS bulbs — standard bayonet (B22) or screw (E27) for general room lighting
- LED candle bulbs — decorative fittings, chandeliers and wall lights
- LED GU10 spotlights — recessed downlights and track lighting
- LED MR16 lamps — low voltage spotlight fittings
- LED corn lamps — high-output replacement for street and industrial HID lamps
- LED PL-C lamps — compact fluorescent retrofit for enclosed fittings
- A-class LED bulbs — the highest efficiency available today in standard domestic formats
If you're replacing halogen GU10 spotlights, MR16 spotlights or halogen capsule lamps, any F or E-rated LED equivalent will cut your running costs significantly — typically by 50–70% — while lasting 15–25 times longer. The new label letter is not a barrier to making a smart, efficient choice.
Shop Energy-Efficient LED Bulbs at Light Shop Direct
Browse our full range of LED bulbs by fitting, shape and efficiency rating. Free UK delivery on all orders over £50.