What are BIAB nails? Here's everything you need to know about the formula that's taking over TikTok

Nail polish used to be simpler. First, there was the traditional formula you could get from Boots, then came gels, acrylics and shellac. Next? BIAB nails joined the party. But in place of simplicity, we now have plenty more choice and innovation when it comes to creating manicures that look great and last the distance.

However, to clear up any confusion, we have everything you need to know about BIAB nails below…

What is BIAB?

The top line: In a nutshell, BIAB is a manicure that's gentler than acrylic, but thicker than regular nail polish and gel polish. The protective shell it creates over nails is designed to encourage natural nail growth and strength underneath, which is why it's been fan-girled across the internet for helping the girl's to achieve longer natural nails. It can also be used to infill nails, without the whole mani being removed and it be used to sculpt extensions on the end of your nails for extra length.

While some fans are still catching on, the formula actually launched in 2015 under vegan nail brand, The Gel Bottle, which was created by Brighton-based founder and professional nail technician, Daisy Kalnina. These days the next-gen formula is everywhere you look. In under a decade, it's built up an A-list following, with JLo, Dua Lipa and Kim Kardashian all opting to wear BIAB. Meanwhile, the hashtag #biab has over 480 million views on TikTok with users sharing their nail journey and try-ons.

As for how it differs from the formulas used by previous manis? We asked Giorgia Cappella, head educator at The Gel Bottle to talk us through the details. For starters, BIAB is a professional-only soak-off soft-gel “specifically formulated to be used as an overlay on the natural nail,” explains Giorgia.

“It was created to provide extra strength and protection against breakages, allowing customers to grow their nails to new lengths,” confirms Giorgia. In terms of appearance, it looks similar to gels and shellac, creating a smooth shiny, manicured finish, but the application process looks a little different.

How is BIAB applied?

Your manicurist will start by prepping the nails (with filing, buffing and cuticle work) and removing any residue on the nail with pure acetone.

The majority of our BIAB colours can be applied to the natural nail but there are some that differ. Lighter shades like Clear BIAB, White BIAB and Milky BIAB require a coat of Rubber Base Coat, while the brand's HEMA-Free BIABs require a coat of HEMA-Free Bond Base. These are then cured like a normal gel base on a low heat mode.

Here's where things start looking a bit different. Rather than traditional-looking liquid polish, the BIAB nail colours come in thicker gels. Rather than a thin coat of your nail colour of choice applied over the nail, your manicurist will apply a thick bead of BIAB, spreading it side to side and dragging the soft gel away from the cuticle. You can choose a natural colour and use BIAB as your base before following with a gel colour on top. Or you can choose from BIABs wide range of colours and make this step your colour coat. Your manicurist will work to avoid creating a thick build-up around the free edge and cuticle, then seal the free edge. You can do this step twice if you want a more opaque finish, building and curing one nail at a time.

Next your manicurist will wipe each nail with alcohol to remove any stickiness, then they may refine the finish of the polish by filing it. This step is crucial for achieving a smooth, even surface before applying your chosen top coat. Your manicurist will remove any dust with a duster brush before applying the final colour you want.

Once you've got the base, you can go in on top with nail art, or if you're just using the BIAB as a base, you can apply any regular gel shade you like on top, then finish with a thin layer of top coat.

How to create infills with BIAB?

For an infill, your manicurist will file the bottom of the polish to create a smoother transition. Next, they'll apply a thin slip layer to help the ball of BIAB (applied next) to self level. This layer isn't cured. The ball of BIAB is then applied close to the bottom of the nail and the brush is used to lightly float the polish from the base up to the free edge to create a consistent-looking coat. This is then tidied with a fine liner brush and cured.

How to create extensions with BIAB?

The extensions are created using clear BIAB, which requires a rubber base coat (mentioned above). This is applied to the ends of the nails and cured on a low heat mode. A form (which is a piece of cardboard that slots under the nail and extends out to create a structure for your extension to be built on) is attached to your nail. Next your manicurist will go in with the clear BIAB to create the rough length and shape you desire. It should cover a third of your natural nail and extend out onto the form. Each nail is done one at a time and cured on a low heat mode. Once hardened, your manicurist will refine the shape and make it perfect using a nail file. They will then apply your BIAB base or top coats as they would in a normal manicure.

How long does BIAB take to apply?

In general it takes slightly longer than other gel services. Your manicurist should spend a good amount of time on perfectly prepping the nail, so block out around an hour and 15 minutes to an hour and a half for the whole process.

What’s the difference between BIAB and shellac or other gels?

“BIAB differs from other gels and patented brands such as ‘Shellac’ due to its formulation. BIAB is not a regular gel polish in itself. It is thicker in consistency and comes in a range of pigmentations, which allow it to be worn as an overlay, a strengthening base for gel colours or as the colour, paired with our extreme shine top coat,” says Giorgia. “Whilst all products are still considered a ‘gel’, we can categorise base coats, gel polish colours and top coats as regular gel formulations, BIAB as a soft gel and Gel Pot [another of the brand's products] as hard gels,” she adds.

What’s the difference between BIAB and acrylics?

“Acrylic nails are created by mixing a liquid (monomer) with a powder (polymer) to create a hard structure as an overlay or an extension to the natural nail. Whilst acrylics support strength and durability, they can be harsh on the nails,” explains Giorgia.

“Gel products alternatively use rays emitted by UV/LED light to turn the liquid gel (monomer) into a hardened gel surface (polymer). As a result gel nails have a more natural look to them and tend to be kinder on the nail due to their flexibility,” she adds.

“BIAB in comparison to acrylics can provide as much strength and protection as an acrylic overlay when applied correctly," says Giorgia. And while they can also create extensions (as above), Giorgia reckons "the hard-gel Gel Pots work better as a gel alternative to acrylic for creating long and strong extensions.”

Is BIAB good for your nails?

“BIAB can be used in thin layers as a base coat to provide an added layer of strength to any gel polish manicure, however it should be applied correctly as a natural nail overlay,” says Giorgia. “We recommend, BIAB is used to mimic the apex of the natural nail, providing the structure that the nail needs to withstand pressure in its stress point and protection against breakages. Used right, BIAB is great for keeping your nails long, strong and healthy,” she says. Plus, the brand added its HEMA-free collection in autumn 2023, removing HEMA, the main allergen that can cause sensitivities in gel nail polish.

How long does BIAB last?

“As with all gel products, maintenance appointments should be regular and consistent in order to ensure the health of the natural nail," says Giorgia who says BIAB will last “anywhere between 2-4 weeks dependant on lifestyle factors.” But if you want to use the product back to back, “we recommend infilling BIAB in order to maintain the strength of the natural nail, whilst always checking the health of the nail and completing a full soak off and new set every 3-4 appointments,” Giorgia says.

How much should it cost?

The cost of your service will differ depending on location and your nail tech's experience, however, “a general advisory is that BIAB overlay services are no less than £10.00 on top of the cost of your gel polish manicure,” says Giorgia (so between around £35 to £80).

How do you remove BIAB?

“As a soft-gel it's a soak-off product,” says Giorgia. However if you've used the BIAB shades that require a rubber base coat, it will need filing off. “BIAB can either be fully soaked off or the bulk of product can be removed using an E-file before a soak off of the final layers can be carried out,” says Giorgia.

For more from GLAMOUR's Senior Beauty Editor, Elle Turner, follow her on Instagram @elleturneruk