E27 vs B22 Bulb Holders: What to Know Before Buying

Quick answer

E27 and B22 describe two different bulb cap types, and a holder built for one will not safely accept the other. E27 is a screw-in cap; B22 is a push-and-twist bayonet cap. Match the holder to the bulbs you already own or plan to buy, then choose the holder style, finish and cable that suit the room.

Buying a bulb holder looks simple until you meet two near-identical fittings with different names. E27 and B22 holders both accept a bulb, both mount to a wall or ceiling, and both can be paired with a shade, yet the bulb you screw into one will not lock into the other.

This comparison sets out what actually differs between the two cap types, where each one tends to be used, and how the choice affects the holder, cable and shade you buy. It also shows how two real holders from the Industville range solve different problems, so you can pick with confidence rather than guesswork.

What E27 and B22 actually mean

E27 is a screw cap: the bulb has a threaded metal base that turns into the holder and tightens by rotation. B22 is a bayonet cap: the bulb base has two small pins that slide into L-shaped slots and lock with a quarter turn. The numbers refer to the base diameter in millimetres, so an E27 base is roughly 27 mm across and a B22 base is roughly 22 mm across.

That size difference is why the two are not interchangeable. A B22 bulb will not grip the threads of an E27 holder, and an E27 bulb is too wide to seat in a B22 socket. Adapters exist, but they add a joint between bulb and holder and reduce the clearance inside a shade, so matching the holder to your bulb from the start is the cleaner route.

• Check the cap type printed on the bulb box or stamped on the bulb base before ordering a holder.
• If you are replacing a holder on an existing fitting, take the old bulb with you or note its cap type first.

Where each cap type is common

E27 screw fittings are widely used across Europe and in many modern and retro-style light fittings, which makes them the easier cap to source when you want a broad choice of LED and decorative bulbs. B22 bayonet fittings remain common in the UK and in older installations, and many households still have a drawer of bayonet bulbs they would rather keep using.

Neither cap is better in principle. The practical question is what your existing bulbs, lamp holders and room wiring already use. Mixing cap types across one room means keeping two sets of spare bulbs, which is a small but real annoyance over time.

• Count how many spare bulbs of each cap type you already own before standardising.
• If a room has several fittings, keeping one cap type across all of them simplifies bulb swaps.

How the holder style changes the decision

Once the cap type is settled, the holder itself becomes the design decision. Cord sets combine a holder with a fabric flex cable, which suits pendants and hanging arrangements where the cable is part of the look. Wall holders mount directly to the wall and suit bedside, hallway and feature-wall lighting where a trailing cable would be unwelcome.

Finish matters as much as form. Brass and pewter tones read warmer and more traditional, while black finishes sit closer to a utility or industrial scheme. Because holder finishes are usually chosen separately from shade finishes, you can either match them closely or deliberately contrast a polished holder against a matte shade.

• Decide whether the cable will be visible; if it is, treat the flex colour as part of the design.
• Order holder and shade finishes together so you can judge the pairing before installation.

Safety, ratings and shade pairing

A holder is a functional electrical component, not just a decorative one. Wall-mounted holders are commonly rated IP20, which means they are intended for dry indoor locations and are not suitable for bathrooms, outdoors or anywhere they may be splashed. If a product listing does not state a rating, treat that as missing information rather than assuming it is suitable for a wet area.

Shade compatibility is the other practical limit. A shade needs a compatible fitting ring and enough internal clearance for the bulb you intend to use, especially with larger decorative bulbs. Where a listing does not give a shade diameter or bulb clearance figure, check the shade's own specification before committing, because a holder and shade that look right together can still fail on physical fit.

• Keep wall holders to dry, indoor positions unless the listing explicitly states a higher rating.
• Confirm the shade's fitting type and internal clearance before pairing it with a new holder.

What it costs to get the cap wrong

The cost of a mismatch is rarely just the price of the holder. You either buy new bulbs in the correct cap, return the holder, or add an adapter that changes the clearance inside the shade. On a pendant, that can mean the bulb sits lower than intended or fouls the shade opening.

The cheaper habit is to decide the cap type first, then buy the holder, cable and shade around it. That sequence also makes it easier to buy several holders at once for a room or a whole floor, so every fitting takes the same bulb.

• Buy the bulb type first if you are still deciding; the holder choice then follows automatically.
• For multi-fitting rooms, order all holders together to keep finishes and cap types consistent.

The trade-offs, stated plainly

• E27 screw cap: Threaded base, wide bulb availability and easy to source in modern and retro fittings. The trade-off is that it is the wrong choice if your existing bulbs and holders are bayonet, and adapters add a joint that eats into shade clearance. Choose E27 if you are buying bulbs fresh or standardising a room on one widely available cap.
• B22 bayonet cap: Push-and-twist pins that lock with a quarter turn, still common in UK homes and older installations. The trade-off is a narrower choice of decorative and statement bulbs compared with E27. Choose B22 if your existing bulbs, fittings or spares are already bayonet and you want to keep using them.
• Cord set vs wall holder: A cord set such as the Chelsea gives you holder and fabric flex as one unit for pendants. A wall holder such as the Brooklyn mounts directly to the wall, with or without a plug, but is IP20 rated and therefore indoor and dry-area only. Pick the cord set when the cable is part of the design; pick the wall holder when you want light without a ceiling drop.
• Holder only vs complete fitting: The Knurled Torch Double Wall Holder is supplied as holder only, so cable, bulb and shade are separate purchases. That gives freedom to tailor the finish and flex, but it also means more decisions and more chances of a mismatch. Buy holder only when you have already chosen the cable and bulb; buy a cord set when you want fewer variables.

Two holders, two different jobs

• Chelsea Cord Set ES E27 Bulb Holder: The Chelsea Cord Set combines an ES E27 bulb holder with a fabric flex cable, and the range is described as a modernised take on the industrial aesthetic with refined curves. It can be paired with Industville shades and Edison LED bulbs, and is available in a choice of finish and cable style. This is the option to choose when the cable will be on show and you want the holder, flex and shade to read as one designed piece rather than three separate parts.
• Brooklyn Wall Holder: The Brooklyn Vintage Wall Mount Bulb Holder is described as a utility-chic update that can be attached to a range of Industville light shades. It is available in Black, Pewter and Brass, with or without a plug, and is IP20 rated. A wall-mounted holder removes the need for a ceiling drop, and the plug option means it can be used without hard-wiring. The IP20 rating confirms it is for dry indoor positions only.
• Knurled Torch Double Wall Holder - Brass - Holder Only: A textured knurled, pointed metal double wall holder with a flat, rounded base, measuring H22 cm x W23 cm. It is supplied as holder only and is described as suited to elegant spaces and feature walls. Because it is holder only, you need to plan the cable, bulb and any shade separately. Its size and sculptural form make it a feature in its own right rather than a discreet fitting.

Which should you buy?

Best for

• Anyone starting fresh with bulbs and wanting the widest choice of LED and decorative options, using an E27 holder such as the Chelsea Cord Set ES E27 Bulb Holder
• Bedside, hallway and feature-wall lighting where a ceiling drop is impractical, using a wall holder such as the Brooklyn Wall Holder in Black, Pewter or Brass
• Rooms where the holder is meant to be seen, such as a brass Knurled Torch Double Wall Holder on a feature wall

Not for

• Households already stocked with bayonet bulbs, unless you are willing to replace them all or accept the clearance penalty of an adapter
• Bathrooms, outdoors or any area where splashes are possible, since wall holders such as the Brooklyn are IP20 rated for dry indoor use
• Buyers who want a single box containing everything, unless they choose a cord set rather than a holder-only product

Settle the cap type first, then let the holder style follow. If you are buying bulbs fresh, an E27 holder such as the Chelsea Cord Set gives you the widest choice and a matched fabric flex. If you need light on a wall rather than from the ceiling, the Brooklyn Wall Holder does the job in dry indoor spaces, with or without a plug. Match the cap, check the rating, and the rest of the decision is simply finish and form.