To use a Dual Voltage Electric LED Bulb E26 in a E27 or B22 environment?

So I bought a Universal LED Bulb that emulates Circadian Rhythm for lighting to help manage my sleep cycles, locally (wherever I am) as well as when traveling.

Most of my time is spent between:

  • US (Currently ordered & Shipped E26) &
  • India (mostly B22 around and newer installations have E27)
  • Some other nations now & then (not long enough to order there)
  • I have a local India store bought (Similar to pic below) B22 to E26/E27 converter I've used before)
    • Wont work with new E26 bulb; appeared it would, but did so for E27.
    • On checking, previous china made bulb model was E27 bought via Amazon US

When I googled why, this was the answer that popped up -

Can A Bulb With An E26 Base Fit In An E27 Socket?
The answer is sometimes. Sometimes an E26 base will fit into an E27 socket, while other times an E26 base will have one extra tread, preventing it from reaching the bottom of the socket and forming a connection.

Question: How do I make it work in India or any E27 / B22 locations ?

  • Find a converter that does B22 to E26 and a E27 to E26 also (Hard find?)
  • Small DIY hack on converter that manipulates / fixes around this E26/E27 difference?

Updated Data: "Standard" bulb base: E26 or E27? Both? https://www.homeownershub.com/maintenance/standard-bulb-base-e26-or-e27-both-266061-.htm

Sarah wrote:

  • E26 (US) are one millimeter shorter and may not make contact with the base. No contact, no light.
  • Longer, E27 bulbs will make contact in the shorter base. I have had the same experience.
  • All my USA purchased lamps worked great in Europe.
  • None of my European lamps or ceiling lights worked in the USA without bulb base adaptors.
  • It has been so long since I purchased them I can't tell you where to go.

The difference of the lamp socket E26 and E27

  • The threads are the same but I believe E27 is a longer base, meaning a European bulb would fit an American socket but the reverse might not be true.

  • I seem to remember a German customer of one of my former employers who brought several lamps over from Germany, and had no problem getting American bulbs to fit.

  • They are the same diameter and thread size. The only difference is that the E26 is 26mm long and the E27 is 27.5mm long.

enter image description here


E26 or E27 Edison Screw?

There is only a 1mm difference between the threads of E26 and E27, so they are virtually identical. Still, it's important to buy the correct bulb certified for use in your country. This is because each country and region of the world, have different certifications. B22 bulbs are also available. They are not as popular, and generally used in the UK, Australia, and India.

An easy reference of what Bulb type is used in major markets is as follows:

United States - E26 Edison Screw
Canada - E26 Edison Screw
Japan, Korea & Taiwan - E26 Edison Screw
Australia - E27 Edison Screw (or B22 Bayonet Cap)
Europe - E27 Edison Screw
United Kingdom - E27 Edison Screw (or B22 Bayonet Cap)

  • For legal, and cost based reasons, the only bulbs we sell/ship to the United States are E26 connector bulbs.
  • E27 bulbs are only available to ship to countries where they are certified. We do not ship, under any circumstances, E27 bulbs to the United States.

"Bulbs have a universal power supply. They will work with electric grid power from 100-240V 50/60Hz"

"The following countries use E27 bulbs:
..India.. "

  • \$\begingroup\$ A set of two adapters should do the job for you. \$\endgroup\$
    – winny
    Commented Jun 26, 2018 at 10:45
  • \$\begingroup\$ @winny - Which ones? In all my searches all adapters are typically B22 to E26/E27 (both) and I cant find any E26 to E27 ones; assuming for both, that the small E26 vs E27 difference (quoted above) becomes a reality. \$\endgroup\$
    – Alex S
    Commented Jun 26, 2018 at 12:59

2 Answers 2


Why not just an e27 socket plug with a travel-plug-set?

There are socket-plugs on nice bendable arms, with switches in the base, and there are decent, strong travel plugs who will support an arm, so you can point the light up no matter where the wall socket (or floor socket in that case) is located.

  • \$\begingroup\$ sorry, I did not see the date, the question popped up in a window near another question, I interpreted as a new, recent question. @Alex-s I hope you have got a good solution by now :) \$\endgroup\$
    – ExploWare
    Commented Dec 11, 2020 at 8:15
  • \$\begingroup\$ Appreciate all inputs, who knows when and how it may help me or someone. Will read up when at laptop. A mobile response: had to pull the bottom metal thing a bit, and it made contact. McGuyvered ways 🙄😂 \$\endgroup\$
    – Alex S
    Commented Dec 13, 2020 at 18:22

If you have a problem connecting E26 bulbs to E27 sockets due to the shortage in length with E26. You can solder a small V shaped plate to the E27 socket base to eliminate the difference in lengths between both. But you have to be careful to prevent contact between the two terminals of either the socket or the bulb. With such solution you have to only buy a B22 to E27 converter and your bulb will work well.

  • \$\begingroup\$ Already have B22-E27 converter, issue is I figured it would do both E26 and E27. Hopefully I can find one that does both and not have to do soldering. PS: Do elaborate on V shaped plate?? Cant visualize. \$\endgroup\$
    – Alex S
    Commented Jun 27, 2018 at 5:24
  • 1
    \$\begingroup\$ A V shaped plate so that one side of it is solder to the base and the other will make the contact with the bulb base terminal, and also act like a spring so that it can adapt with different bulb positions. By the way some E27 socket some times have their base terminal already a samll plate, you can gently bend it upwards so that you can eliminate the misalignment. \$\endgroup\$
    – ahm_zahran
    Commented Jun 27, 2018 at 6:49
  • \$\begingroup\$ Yes - "E27 socket some times have their base terminal already a samll plate, you can gently bend it upwards so that you can eliminate the misalignment" It looks like a metal blade/ plate, which could be bent upwards a little, only if I can find the right way / tool to get into do that :) Given the limited area within. \$\endgroup\$
    – Alex S
    Commented Jun 27, 2018 at 7:48
  • \$\begingroup\$ There is no need for special tooling to do that, all you need is small pliers and a piece of wisdom to prevent a short cuircuit. \$\endgroup\$
    – ahm_zahran
    Commented Jun 27, 2018 at 8:34
  • \$\begingroup\$ ... and the wisdom to turn off the power before you go poking pliers into a lamp holder! \$\endgroup\$
    – Simon B
    Commented Jan 4, 2019 at 16:09

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