Bio Ionic Long Barrel Curling Iron Review

We loved the long, luscious curls of this Editor's Pick, but the control buttons are kind of confusing

Bio Ionic Curling Iron on colorful background
Bio Ionic Long Barrel
Photo: Laura Murphy/Consumer Reports

Price paid: $140
Where to buy: Amazon, Bio Ionic, Ulta, Walmart
Material: Ceramic
Barrel length: 6½ inches
Multiple temperature settings: Yes, 6
Cord length: 9 feet
Dual voltage: No
Auto shutoff: Yes, after 1 hour
Warranty: 1-year limited
Safety certification: TÜV Rheinland

The Bio Ionic boasts that its Long Barrel curling iron has a 2-inch-longer barrel than the average curling iron’s, “for longer hair and ease with back of head styling.” It comes with instructions that include temperature suggestions depending on hair type. The six settings are 250° F and 280° F, recommended for fine hair; 320° F and 360° F, recommended for normal hair; and 390° F and 430° F, recommended for thick or coarse hair. 

How it works: After plugging in the iron, you must press the power button to heat it up. You can adjust the temperature setting via buttons labeled “+” and “-.” The settings are shown on a strip on the side of the barrel. The setting you choose will light up, then blink until the barrel reaches your desired temperature, then the light holds steady. You can lock in the temperature—meaning disable the + and - buttons—by pressing the power button twice. A lock icon will illuminate on the settings. We found that the barrel takes about 22 seconds to heat up and, after it was turned off, about 13 minutes to cool enough that it was safe to touch. 

The instructions also describe a patented technology that Bio Ionic has incorporated into this iron: NanoIonic Mineral Technology. Purportedly, this technology generates negative ions that “micronize water molecules, allowing for faster styling time”—up to 50 percent faster, according to the brand—as well as seals and smooths the cuticle and hydrates hair. 

Our biggest gripe: Angela, who has layered shoulder-length hair, felt that the Bio Ionic was way too big for her hair. 

“That said,” she conceded, “it’s nice and light.”

Perry and Angela weren’t crazy about the fact that you have to lock the buttons to avoid pressing them. It’s true that if you don’t lock the buttons, you’re likely to press them while styling your hair because of their placement on the handle, but I didn’t think this was a deal breaker. 

With continued use, though, Ginger and I discovered that you have to hold the power button for a few seconds to turn the iron on. This is definitely a flaw because there’s nothing in the directions that suggest that users should do this. We both thought the iron had died until we played around with it for a while and figured out how to turn it back on. 

What we liked: Among those of us with longer hair in the group, the curling iron was a hit.

“My hair is waist-length,” Ginger said, “and this one had plenty of real estate to help keep my hair flat on the iron, which, for me, results in nicer curls.”

Four of the five evaluators felt that the curling iron yielded shiny, healthy-feeling results. We’re not sure whether the aforementioned technology is the reason for this—there’s also the fact that the iron has a lot of temperature options, making it easy to customize for your hair. 

“If I just need to refresh a couple curls here and there,” Ginger said, “then I typically like to use less heat than I used on the first day of styling.”

Time lapse of Laura curling her hair with the Bio Ionic Long Barrel.
Video: Laura Murphy/Consumer Reports

Read about CR’s curling iron evaluation process and see our individual curling iron reviews (below).

This product evaluation is part of Consumer Reports’ Outside the Labs reviews program, which is separate from our laboratory testing and ratings. Our Outside the Labs reviews are performed at home and in other native settings by individuals, including our journalists, with specialized subject matter experience or familiarity and are designed to offer another important perspective for consumers as they shop. While the products or services mentioned in this article might not currently be in CR’s ratings, they could eventually be tested in our laboratories and rated according to an objective, scientific protocol.

Like all CR evaluations of products and services, our Outside the Labs reviews are independent and free from advertising. If you’d like to learn more about the criteria for our lab testing, please go to CR’s Research & Testing page.

When you shop through retailer links on our site, we may earn affiliate commissions. 100% of the fees we collect are used to support our nonprofit mission. Learn more.