TP-Link Kasa Filament Smart Bulb review

The TP-Link Kasa Filament Smart Bulb (KL50) ticks all the boxes when it comes to vintage style and affordability.

TP-Link Kasa Filament Review
(Image: © TP-Link)

Top Ten Reviews Verdict

Cheap, cheerful and offering a great retro look for any exposed light fittings you don’t want hidden under a shade, the KL50 is an affordable way to get your classic lamp and chandeliers connected without ruining their old-school aesthetic.


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    Great retro style

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    Simple set-up

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    App can be problematic

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The best smart lighting might make you think of futuristic, color changing bulbs. But what if you want something a little more refined, to match a vintage-inspired interior design. The TP-Link Kasa Filament Smart Bulb (KL50) offers just that – and a price that won’t break the bank.

There’s an industrial look to some smart bulbs. Their clouded LED glass housing can be a bit of an eyesore, especially if they’re hanging out and exposed from an otherwise-vintage styled lamp base or fitting.

The TP-Link Kasa Filament Smart Bulb (KL50) takes a different approach. While its base is a little chunky (as is common with smart bulbs – the ‘smart’ stuff has to go somewhere), it’s actual illuminated area has a classic look, with old-school filaments doing the work of brightening up your room.

Set up is simple – supporting Android and iOS apps, there’s no need for an additional bridge unit to connect your light to the app over Wi-Fi, making for a relatively painless set up process – at least when the app is working as it should.

Even with the retro stylings though, it’s as connected as any competitor, working alongside smart home grouped gadgets, If This Then That routines, and voice assistants including Alexa and Google Assistant.

  • White bulb in 2700K temperature, Amber in 2000K
  • White bulb 600 lumen brightness, Amber 400 lumen
  • 15,000 hour bulb life

The KL50 comes in two types (a bright white and a warmer amber – there are no color changing options here) and two fitting options – an E27 screw-in or a B22 bayonet lock-in. These are standardised in size, and should fit the majority of light fixtures and lamps out there.

Both the amber and white bulbs are slightly different in fitting style, with the white literally using a white casing, and the amber finished with a brass effect.

Both, however, make use of a crossed-filament illuminated section. While the white has a 2700K temperature (a slightly more energized look), the amber is warmer at 2000K. Both are 7W energy saving in output, but they appear much brighter than that, closer to a 40W in old-school standards, and quite comfortable to read by. And, through the app or paired voice assistant, both are dimmable.

  • iOS and Android apps
  • Scheduling functionality
  • Energy monitoring tools

The Kasa iOS and Android apps for the TP-Link Kasa Filament Smart Bulb are among the quickest we’ve used to set up a bulb, pairing almost instantly and quickly adding a firmware update to the bulbs at the same time.

You’ll get relatively-standard control options in the Kasa app. These include brightness and power controls, as well as a scheduling option to fire up the bulb at certain brightness levels at different times of day.

What is unusual however is an included energy monitoring area of the app. It’ll tell you how much energy you’ve saved by using the KL50 as compared to a standard 40W bulb, in kW per hour. However, as it doesn’t know your energy providers tariff, it can’t establish precise figures on how many cents you’ve saved. Still, it’s an interesting tidbit for the green-conscious.

  • Warm, gentle glow
  • Great price to performance
  • Some voice control hiccups

Considering it’s substantially cheaper than similar bulb brands, the KL50 is a delight to use. Its stripped-back feature set belies a relatively stable connection, and a great-looking, warm-glowing bulb. You’d happily leave a shade off this thing and let your visitors see the bulb itself in all its glory.

Where things became a little more difficult was when pairing the bulb up with a smart assistant. Alexa integration especially proved difficult – the Kasa app just couldn’t complete the Alexa pairing process, and so we had to jump into Amazon’s own Alexa app to finish the job. This is despite the Kasa app suggesting it could all be done within the bulb’s own app. Once paired however, it did work well with voice assistants, and could easily be added to smart home room groups ad IFTTT (If This, Then That) routines.

At such a low price point, the TP-Link Kasa Filament Smart Bulb is an easy sell. It’s easy to set up, reliably stable in terms of connectivity, has sensible app features and gives off a welcoming glow.

It isn’t, however, quite as fully featured as the bulbs from its key rival Philips. Hue bulbs can now also be bought in filament styles (as well as in color changing, strip and portable options, among others), but come with wider ranging third-party app support. They’re also significantly more expensive. But if you’ve already got Hue bulbs in your house, for the sake of centralized app simplicity, you may want to stick with the one brand.

Gerald is an expert in Home and Smart tech. He's a contributor to Top Ten Reviews, and currently works for our sister site, TechRadar.