BIAB Is the Celeb Secret for Long, Strong Nails—Here's the 411

In a world where long, almond-shaped nails seem to be everywhere we look, it’s only natural to consider heading to a salon for professional nail extensions. After all, with a little extra length, so many of the season’s prettiest nail art ideas become that much more achievable.

The question that remains when you book, though, is which type of nail extensions will you get. While acrylics may be your first thought, we’re here to remind you of—or introduce you to—BIAB nails (AKA Builder in a Bottle). Not familiar? Keep reading to learn more about the trending nail technique, straight from nail experts Brittney Boyce, Natalie Minerva, and Rita Remark.

What Is BIAB?

"Builder in a bottle is a soak-off sculpting gel for nail extensions,” Boyce says. “On the technical side, builder formulas are oligomers. That means the monomer and polymer are already mixed.” Once the builder is applied, it’s cured by an LED or UV lamp, which bonds it to your nail plate. 

What makes BIAB particularly special is that it’s self-leveling. According to Boyce, the self-leveling formula makes it easier to shape extensions that look and feel like real nails. “Often times other nail extension options can look thick and lumpy,” she notes. What’s more, BIAB nails are flexible, unlike acrylics. “Because it’s flexible like a soft gel, it’s not as prone to damaging breaks, cracking, or brittleness,” she says. “The application and removal process are also not as damaging to your natural nails.” She prefers to use ORLY’s Builder in a Bottle ($40): “It doesn’t have a strong odor that can make the job unpleasant,” she shares.

Don’t be mistaken, though—BIAB isn’t only for achieving length. “​​BIAB is a thicker gel used to build up a nail, whether it be natural nails or for creating an extension,” Minerva says. “The nice part about it is it reduces the number of tools you need since the builder is applicable with the bottle brush.” Remark points out that builder gel can add strength, so if your natural nails are the length of your choosing but sensitive to breaks, BIAB nails can help. 

How Is BIAB Applied?

BIAB nails can be applied in one of two ways: the Perfect Form or the Fast Form. 

“The Perfect Form slides under the nail and hugs it for precision,” Boyce says. “It's easy to customize the length with them, and there's a unique role positioning that adapts to the curvature of the nail so it looks very natural.” Once the Perfect Form is affixed under the nail, the technician applies BIAB to sculpt the extension, cures it, then removes the form before applying a second layer to add strength and durability. 

Then there are the Fast Forms. “The Fast Forms look like long press-on nails with tabs on the side,” Boyce says. “This allows nail technicians to apply extensions relatively fast and helps them achieve that perfect curvature each and every time.” Where Perfect Forms are affixed beneath the nail, Fast Forms are applied overtop. “The nail technician will prep your nails as normal, then apply Builder in a Bottle on the inside of the forms to the desired length, place them on the nail allowing the gel to cover the nail, flash cure for 10 seconds, examine the nail, then finish curing for 30 more seconds,” Boyce says. “Once it's affixed, they pop off the Fast Forms and continue as normal by applying a second layer of Builder.”

How Much Does BIAB Cost?

Like all beauty treatments, the cost of BIAB nails varies based on location and the nail tech’s experience. “In Los Angeles, good nail techs who provide Builder gel extensions typically charge at least $200,” Boyce says.

Meanwhile, Minerva says that, although she doesn’t work in the salon anymore (so she can’t say with certainty), she imagines that the cost of BIAB nails is more or less the same as a full set of extensions.

How Long Do BIAB Nails Last?

Like regular gel nails, BIAB extensions can last between two and four weeks, depending on how fast your nails grow and how hard you are on them. “For clients with Builder, I always recommend a fill rather than a full removal until they are ready to go completely natural,” Boyce says.

Are BIAB Nails Safe?

Of all the different types of nail extensions, Boyce, Minerva, and Remark all agree that BIAB is the safest available. “I always prefer gel nails over [traditional] acrylic for me, personally, since I find that gel has more pliability, and therefore moves and bends with your natural nail much better,” Minerva shares.

BIAB vs. SNS vs. Acrylic

Now that you’re up to speed on BIAB, let’s compare it to SNS and acrylic. “These are all forms of acrylic, just in different states,” Remark says. “BIAB is acrylic in gel form. Classic acrylic is in a liquid and powder form, and SNS is a ‘dip’ acrylic powder plus nail adhesive.” 

Of the three, BIAB is the newest technology, which is part of why it’s surging in popularity. Still, they all have their benefits. “Where SNS and acrylic tend to be more rigid and strong enhancements, best for soft and splitting nails, BIAB or builder gel enhancements are more flexible, natural nail coatings, great for strengthening and adding length,” Remark says.

Minerva adds that she uses BIAB to encapsulate 3D elements in her nail looks; doing so makes the elements more secure and ultimately protects her art.

The Final Takeaway

If you’re looking to achieve longer, stronger nails that look and feel natural, BIAB nails are a great option. “It’s applied like a soft gel, has the hardness of a hard gel but flexibility of a soft gel, and is removed by soaking off,” Boyce says. “Compared to hard gel or acrylics, it’s faster to apply and much more comfortable to wear.”