A B22 to E27 adapter lets an older bayonet fitting accept an E27 screw-in bulb without replacing the lamp holder. It is useful for a table lamp, pendant or other indoor fitting when the socket is sound but the bulb choice is limited.
Key takeaway
Check the fitting type, voltage, available space and bulb rating first. The adapter changes the cap connection; it does not change the fitting's voltage, wattage limit or installation requirements.
What a B22 to E27 adapter changes
B22 is a bayonet cap with side pins. E27 is a screw-in cap. The adapter provides the E27 thread while its B22 end fits the existing socket.
It is a connection adapter, not a transformer and not a replacement for damaged wiring or a loose lamp holder. The Future Light B22 to E27 lamp holder adaptor is listed for 230 VAC indoor use, with a durable plastic body and a 60 mm length.
B22 vs E27: what is the difference?
The cap type describes how the bulb connects to the fitting. A B22 bulb pushes in and locks with a twist, while an E27 bulb screws into a threaded holder. Neither cap is automatically brighter, safer or more efficient. Those decisions depend on the bulb and fitting specifications.
| Check | B22 | E27 |
|---|---|---|
| Connection | Bayonet pins and twist lock | Screw thread |
| Common use | Older lamps and fittings | Many modern lamps and decorative bulbs |
| Adapter needed? | Only when the fitting and bulb caps differ | Only when the fitting and bulb caps differ |
| What still needs checking | Voltage, wattage, dimensions, dimming and indoor/outdoor suitability | |
If you want to compare bulb shapes and finishes after checking the cap, browse the LED bulbs collection.
How to fit the adapter safely
Switch off the light and isolate the circuit before handling the fitting. Remove the existing bulb and inspect the B22 socket for cracks, scorching, looseness or damaged contacts.
Push the B22 end into the socket and twist it into place. Screw in an E27 bulb that stays within the fitting's stated wattage and clearance limits. Do not force a bulb or use the adapter in a fitting that is not stable.
Is a B22 to E27 adapter safe?
It can be safe when the adapter, socket and bulb are suitable for the same electrical conditions and the fitting is used indoors as specified. The adapter does not correct an old or damaged holder. Stop if the socket is loose, the contacts are burnt, the bulb sits at an angle or the fitting becomes unusually hot.
Use a qualified electrician for fixed-wiring changes, damaged fittings or any installation where you are unsure about isolation and load limits.
For a direct product example, review the adaptor specifications before choosing a bulb, then compare compatible options in the adaptors collection.
Choose the bulb after checking the fitting
Once the cap connection is solved, choose the light itself. Confirm the bulb's voltage, wattage, shape and length. A bulb can fit the thread and still be too large for a shade or exceed the fitting's limit.
A B22 LED bulb is still useful when you are keeping a B22 fitting elsewhere in the home. The 15W LED B22 bulb shows why cap type should be checked before shopping, while an E27 filament bulb may suit a different fitting after conversion.
When should you replace the fitting instead?
An adapter makes sense when the holder is in good condition and you want a reversible indoor change. Replace or repair the fitting when it is damaged, loose, heat-marked, incorrectly mounted or unsuitable for the room. An adapter will not make an outdoor fitting weatherproof, and it will not solve a wiring fault.
For decorative lamps, check the shade opening and the bulb's visible shape before ordering. A clear filament E27 bulb can look very different from an opal bulb even though both use the same thread.
If the fitting is part of a cabinet or workbench project, the existing under-counter lighting range is a better next step than forcing a bulb adapter into the wrong application.
If the conversion is for a pendant or table lamp, compare the bulb shape as well as the cap in the LED bulbs range.
E27 bulb choices after conversion
E27 opens up more bulb choices, including decorative filament styles and different finishes. The bulb still needs to suit the fitting, shade and intended light level.
The 4W E27 LED filament bulb is one example of the screw-in format. Treat it as a product example, not a universal recommendation: confirm the bulb's colour, brightness and dimensions for your room.
Common mistakes to avoid
- Using an adapter to hide a damaged or loose B22 holder.
- Assuming the adapter changes voltage, wattage or dimming compatibility.
- Choosing a bulb that touches the shade or fitting.
- Using an indoor IP20 component in an exposed outdoor location.
- Forcing the adapter when the bayonet pins do not line up.
Frequently asked questions
Can I use a B22 to E27 adapter with an LED bulb?
Yes, if the adapter and the fitting are suitable for the bulb's voltage, wattage and physical size. The adapter changes the cap connection; it does not change the bulb's electrical requirements.
Are B22 to E27 adapters safe?
They can be safe when used indoors with an undamaged B22 socket, a suitable adapter and a bulb within the fitting's limits. Do not use an adapter to compensate for burnt contacts, loose wiring or a damaged holder.
What is the difference between B22 and E27 bulbs?
B22 bulbs use bayonet pins and lock with a twist. E27 bulbs use a screw thread. The cap type is separate from brightness, colour temperature and energy use.
Can I use the adapter in a ceiling light?
Only if the ceiling fitting is an indoor B22 fitting in good condition and the adapter and bulb fit without fouling the shade or mounting. Ask an electrician if the fitting is loose, damaged or requires wiring changes.
Does a B22 to E27 adapter change the voltage?
No. It only adapts the physical connection. Check the fitting, adapter and bulb voltage separately before use.
Can I remove and reuse the adapter?
You can remove it and use it in another suitable indoor B22 fitting, provided it remains undamaged and the new fitting has the required clearance and electrical rating.
