When you’re choosing light bulbs, start with the fitting, the output you need, and whether the lamp is on a dimmer. GU10, E27, E14 and bayonet light bulbs all do the same job, but the wrong cap or a non-dimmable lamp bulb is where the call-backs start. LED light bulbs are usually the first swap for most replacements. Filament or decorative versions make more sense where the fitting is on show and the look matters.
Integral LED Classic GU10 Lamp - 3.4W Daylight 400lm 10 Pack
3.4W LED GU10 daylight lamp, 400lm, non-dimmable, 10-pack
Wessex LED GU10 Dimmable Bulb - 3.6W Cool White 345lm 5 Pack
3.6W LED GU10 dimmable bulb, 345lm cool white, pack of 5
Wessex LED GU10 Glass Bulbs - 3W Warm White 345lm 5 Pack
5-pack of 3W warm white GU10 LED glass bulbs, 345lm
Wessex LED GU10 Glass Bulb Lamp - 3.6W Warm White 345lm 5 Pack
Warm white 345lm LED GU10 lamp, non-dimmable, 5-pack
Wessex LED A60 GLS Dimmable Bulb - 7.3W BC Warm White 806lm 5 Pack
Dimmable 7.3W warm white LED bulb, 806 lumens, BC cap, 5 pack
Wessex LED A60 GLS Dimmable Bulb - 7.3W ES Cool White 806lm 5 Pack
Dimmable 7.3W cool white LED bulb, 806 lumens, ES cap, 5 pack
Integral LED Classic MR16 GU5.3 Light Bulb - 380lm 2.7W 2700K Non-Dimmable 3 Pa…
LED MR16 GU5.3 380lm 2.7W 2700K warm white, non-dimmable, 3-pack.
Integral LED Max Efficiency A60 GLS Bulb - 4.3W 806lm BC 2700K
Integral LED Max Efficiency GLS bulb, 4.3W, 806lm, BC, 2700K warm white.
Wessex LED GU10 Bulbs - 3W Warm White 345lm 5 Pack
5-pack of 3W GU10 LED bulbs, warm white 345lm, non-dimmable
Philips LED A Shape Lamp - 13W ES (E27) 1521lm
Philips 13W ES LED lamp, 1521lm warm white, non-dimmable
Start with the space you’ve got and how the lamp will be used, then narrow the light bulbs from there. A tight fitting or shallow shade rules out some shapes straight away. A dimmer changes the choice again, because not every lamp bulb behaves well at low output. Most call-backs come from the wrong cap or a bulb that looks right on paper but sits awkwardly in the fitting. If you’re replacing like for like, keep the cap and size consistent first, then decide whether you want a standard LED, a dimmable option, or a more decorative finish.
For most jobs, you narrow light bulbs by format before anything else. LED light bulbs are the usual pick when you want lower running cost and less heat, but the lamp still has to suit the bulb, and any dimming gear needs checking.
Bayonet light bulbs still make sense when you’re swapping like for like and want the same cap back in without changing the holder. Screw light bulbs, including e27 light bulbs and e14 light bulbs, cover the same sort of replacement work. E27 suits larger general-purpose fittings. E14 is more common in smaller decorative lamps. GU10 light bulbs are the one you reach for when the fitting takes a mains spotlight lamp, though the wrong type is less forgiving once it’s in hand.
The first check is the fitting and the lamp body around it. That tells you if you’re buying a straight replacement or changing the look of the job.
After that, check whether it needs to dim cleanly and whether LED light bulbs make sense for the running cost. A cheap swap that flickers on a dimmer gets called back.
Shape matters too. A shallow shade or tight lantern usually rules out the bulkier options. Decorative lamp bulbs are picked more for the finish than the output.
If the job is moving away from lamps altogether, Downlights are the next call. If you only need the light to come on when someone’s there, Motion Sensors may be the better buy.
Once you’ve settled the bulb spec, the next call is usually the gear around it - the fitting, any trim or screen, and whether the lamp needs a matching control or sensor. That keeps a simple replacement from turning into a second visit.
A lot of call-backs come from mixing the wrong bulb with the wrong fitting, or leaving the control side unresolved. If the job includes downlights or a timed circuit, sort those parts with the light bulbs so you’re not back chasing compatibility after the fact.














