Some bulbs are meant to be hidden behind a shade. Filament bulbs are meant to be seen. With their glowing threads behind clear or amber glass, they turn a bare pendant, a cage light or an open wall light into something finished, and they are the reason an industrial lamp looks warm rather than cold.
Choosing one is about three things: the shape, the colour of the glass and the light, and where the bulb will be on show. Here is how to get each one right.
On this page
- What a filament bulb is today
- The shapes, and what each suits
- Clear, amber or gold glass
- Colour temperature and brightness
- Where a filament bulb belongs
- Dimming filament bulbs
- In short
- Common questions
What a filament bulb is today
The original Edison bulbs used a carbon filament that glowed because it was red hot, and wasted most of its electricity as heat. Today's filament bulbs are LED: thin strips of tiny LEDs arranged to look like the old wire filaments. They give the same visual effect, run cool to the touch and use a fraction of the power.
All the decorative bulbs we sell are LED. If you are replacing an old carbon-filament bulb, an LED filament bulb in the same shape and cap is a direct swap. Our guide to bulb fittings explains which cap your fitting takes.
The shapes, and what each suits
Filament bulbs are named by shape and diameter in millimetres: ST64 means a teardrop shape 64mm across.
| Shape | Code | Looks like | Best in |
|---|---|---|---|
| Classic | A60 | The standard pear-shaped bulb | Lamps where the bulb shows only a little |
| Edison teardrop | ST64 | Tall, narrow, slightly pointed | Bare pendants, cage lights, industrial wall lights |
| Globe | G95, G125 | A sphere, from small to very large | Single pendants on a long cable, exposed sockets |
| Tube | T30, T45 | A long slim cylinder | Narrow glass shades, picture-light style fittings |
| Candle | C35 | A slim flame shape | Chandeliers, candle-arm wall lights |
Our E27 Filament Bulb comes in thirteen shapes, from Classic, Edison, Globe and Tall to novelty Heart, Star and Love, so you can match the silhouette to the fitting. For multi-arm fittings, the E14 Candle Bulb comes as a C35 Classic or a C35L Long-Tip, in 4, 8 or 12W, and in packs of 4 or 10 so every arm matches.
A rule for size
The bulb should look deliberate next to its fitting. A small A60 in a large open cage looks lost; a G125 globe in a narrow glass shade will not fit at all. Before ordering, check the opening of the shade and the space between the socket and the shade's rim.
Clear, amber or gold glass
- Clear glass shows the filament crisply and gives the brightest light for the wattage. It suits glass shades, where the bulb is seen through a second layer of glass.
- Amber or gold-tinted glass warms the colour of the light and softens the glare of the filament. It is the classic vintage look, ideal for bare bulbs at eye level. The tint absorbs part of the light, so expect a softer glow.
- Smoked glass darkens the bulb further for a moody, low accent. Pure decoration.
Our Gold Edison ST64 Bulb uses an amber gold-tinted glass and is available in Warm Yellow, Warm White 2700K or White 6000K.
Colour temperature and brightness
Filament bulbs are bought for warmth, so choose the warmest option your room allows.
- Very warm, amber (often sold as warm yellow or extra warm): candle-like, for bare bulbs in a living or dining room in the evening.
- Warm white, 2700K: still warm, a little clearer, a good everyday choice.
- Cool white: rarely right for a filament bulb on show, because it makes the glowing filament look harsh.
Decorative filament bulbs are not designed to light a whole room. Use them where the bulb is part of the design, and let other fittings provide the bulk of the light. Our guide to how many lumens you need shows how to build that total, and our guide to colour temperature explains which tone suits each room.
Where a filament bulb belongs
Bare and glass pendants
The natural home of the filament bulb. A clear glass shade such as the Vintage Globe Glass Pendant or the Vintage Bell Glass Pendant frames the filament; both take an E27 bulb that is not included, so you choose the shape. For a table, the Vintage Smoked Glass Cluster, as a single pendant or a 3 or 4-light cluster, is designed around a warm filament bulb behind smoked glass.
Exposed-socket lamps and wall lights
Where there is no shade at all, the bulb is the whole design. The Black Socket style of our Wood Table Lamp and industrial wall lights such as the Retro Staircase Wall Light are made for a shapely bulb: a Globe or a Tall ST64 rather than a plain Classic.
Chandeliers and candle arms
Multi-arm fittings need small candle bulbs, all identical. Our Wrought Iron Chandelier, Farmhouse Chandelier and European Iron Chandelier take E14 bulbs: buy a matching pack so that no arm is brighter or warmer than the next. Browse chandeliers.
Inside a closed shade
Here a filament bulb is wasted: no one will see it. A plain frosted LED of the same cap gives more light for less money.
Dimming filament bulbs
Dim filament bulbs and they look even better, closer to candlelight. Two conditions:
- The bulb must be sold as dimmable. Our E27 Filament Bulb is.
- The dimmer must be made for LED. Older dimmer switches were designed for the high loads of incandescent bulbs, and a few LED bulbs on them can flicker, buzz or refuse to dim low. An LED-compatible dimmer, usually trailing-edge, solves it.
If your bulbs already flicker, our guide to why LED lights flicker walks through the causes.
In short
- Filament bulbs are for fittings where the bulb shows.
- Pick the shape for the fitting: ST64 or Globe for bare pendants, C35 candles for chandeliers.
- Amber glass for a warm vintage glow, clear glass inside glass shades.
- Choose warm or extra warm light, never cool, for a bulb on show.
- Dim them on an LED-compatible dimmer.
- Let other fittings do the heavy lighting.
Common questions
Are filament bulbs LED ?
Modern ones are. They use strips of LEDs shaped like old wire filaments, so they look vintage but run cool and use far less electricity than the original carbon-filament bulbs.
What is an ST64 bulb ?
An Edison teardrop bulb 64mm across: tall, narrow and slightly pointed. It is the classic shape for bare pendants and industrial cage lights.
Are filament bulbs bright enough to light a room ?
Usually not on their own. They are designed to be looked at, and amber glass softens the light further. Use them as accents and rely on ceiling lights, lamps or wall lights for general light.
Can I dim LED filament bulbs ?
Yes, if the bulb is sold as dimmable and your dimmer is designed for LED. On an old incandescent dimmer they may flicker or not dim fully.
Which bulb should I use in a chandelier ?
Usually an E14 candle bulb, the same model and colour on every arm. Check the cap your chandelier takes first: some take E27 or G9 instead.
Do I need a filament bulb in a pendant with a shade ?
Only if the bulb is visible, through clear glass or below an open shade. Inside an opaque shade, a plain LED bulb gives more light for less.
Still unsure ?
Send us the name of your fitting or a photo of its lampholder at contact@thelightheritage.com and we will tell you which bulb shape and cap to order. We answer every message ourselves.
Browse our bulbs, the E27 Filament Bulb, the Gold Edison ST64 and the E14 Candle Bulb, or the fittings that show them off: pendant lights, antique brass and ribbed glass and chandeliers. For the industrial look as a whole, see our guide to industrial lighting.
