My Friends Keep Asking If I've Had Filler, But It's Actually This Lip Liner That I've Been Gatekeeping
For effortless lip definition and subtle volume, Merit Signature Lip Liners are my new makeup-bag essential.
Earlier this week, our office manager told me my makeup looked great, and a few hours later, a fellow beauty editor looked me dead in the eye and told me, "That lip liner is really working for you." Yesterday, on my weekly neglected-WhatsApp-inbox check-in, I realised that I had missed a group chat conversation between my friends about whether or not I'd had lip filler. So, after all of the compliments and debate, I'd like to take this moment to declare that no, I have not had lip filler. I've just been wearing Merit Signature Lip Liner.
When I found out that Merit Beauty was launching a lip liner, I had mixed feelings. I adore everything that the brand touches thanks to its lazy-girl-approved formulas and low-fuss ethos. But a Merit lip liner? I wasn't sure. You see, I consider myself Merit's number one fan. I find great joy in aesthetically appealing products, I adore comfortable formulas that look natural on the face and, crucially, I prioritise products that are seriously quick and easy to apply. I find lip liners fiddly by nature, and because they require some level of precision, they just add an unwanted step into my makeup routine.
But that was then, and now Merit Signature Lip Liner has become a permanent addition to my makeup bag, and I can officially confirm that it's the most mind-blowing lip product I've ever used. It's not a lip liner in its truest form, but it's also more than a lip contour (much like the cult Rhode Peptide Lip Shape). It shapes, contours and creates the illusion of fuller lips, sure, but it does it all with an unrivalled sense of ease and a very convincing finish. And it's so good that Misty Copeland even wore it on her lips at the Oscars. Here's what to know.
Merit Signature Lip Liner, Reviewed
The Product
Let's start with the packaging and the product itself. At face value, Merit Signature Lip Liner looks just like any good lip liner does. It is a wind-up pencil, so you don't have to mess around with any sharpening—perfect for those who, like me, never have a sharpener to hand and instead just throw blunt pencils in the drawer to be forgotten about. And, as is always the case with Merit products, it looks beautifully chic.
The one visible difference between this and other lip liners out there, however, is the rounded nib. Rather than a super-pointed, sharp, pencil-like tip, Signature Lip Liner has a slightly thicker (but not too thick) nib that is rounded for smooth, easy, non-precise application. The beauty of this product is that it isn't designed for precision, meaning it's almost unbelievably easy to use.
The Finish
Merit actually shared the original brief for Signature Lip Liner on Instagram. It stated that the product should be:
- "Sheer, buildable and comfortable enough to wear every day".
- "A soft gel formula that doesn't tug or crumble".
- "Hydrating, so that lips feel soft and moisturised".
- "Versatile, so you can use it as a liner or to fill in lips all over".
The brief also stated that the formula should not be "dry, stiff or crumbly" and that the brand never set out for the liner to be "highly pigmented or long-wearing".
The result? A formula that is creamy and glossy in finish and that deposits enough pigment to make a difference, but not so much that it would ever cause application issues. Merit clearly stated that if you use traditional lip liners often, this formula will likely not be for you, which, frankly, speaks to me as a lip-liner hater. This is a liner for makeup minimalists.
The Application
If I haven't made it clear enough already, I'm totally inept when it comes to makeup application—my hands are clumsy, and I don't have a single artistic bone in my body. Because I'm so scared of lip liner, last week, I organised a visit to one of the most talented experts around, makeup artist Zoë Taylor, so that she could school me on how to use the new Merit liner (you can also read our more in-depth guide on how to apply lip liner, too).
She told me that the key is not to get too caught up in the concept of overlining, and instead, to follow the natural outline of my lip and concentrate the product more towards the outer corners, filling from the outside in. She assured me the glossy, gel-like formula will do the rest. The one tip she did give me, however, was to stop trying to accentuate my cupid's bow with liner. "Just draw straight across and round your cupid's bow off," Taylor told me. "This creates the illusion of more fullness."
Armed with all the information I needed, I went home and tried it for myself. Unlike every other lip liner I've ever used, this one glides on with gloss-like ease. And I say lip gloss here because the finish isn't particularly creamy; it has a water-like level of hydration that imparts a dewy, diffused sort of pigment. This quality makes it sheer on first swipe, but beautifully buildable.
The Results
Once I've traced the outline of my lips, rounded off my cupid's bow and filled in the corners (leaving the middle sections bare), I've been applying Merit Shade Slick over the top; one of my favourite tinted lip oils ever. Merit actually launched four new shades to accompany the liners, dubbed "The Sheens". Each has a slightly pearlescent shimmer to further the illusion of fullness. My favourite pairings are Signature Lip Liner in Bespoke with Shade Slick Sheen in Twin Set (below) and Signature Lip Liner in Beverly Hills with Shade Slick Sheen in Biarritz (above).
And as for the lasting power? I appreciate Merit's transparency with this. The brand never promised that Signature Lip Liner would last ages; it's a hydrating formula with a sheer, gloss-like finish, so it's never going to deliver the staying power of a matte lip liner. Having said that, I'm pleased to say it lasts a lot longer than I thought it would. After applying first thing in the morning, I find myself topping up my Shade Slick maybe once every hour or two (depending on how much I've been talking, eating and drinking), and reapplying my Signature Lip Liner perhaps every three or four hours. But I want to make it clear here that this liner does not dry out or flake like others. Instead, it simply gradually fades away without any cracking or smudging.
One thing to note here is that because of the super-hydrating, gel-like nature, I find myself using more product than usual. This isn't a problem, considering that you just have to twist the bottom of the pencil up whilst applying, but it's worth noting that you can expect to get through it quicker than you would a traditional lip liner.
All in all, I'm a woman obsessed. I truly never thought that lip liner would be a product for me. I can't apply it, and I've never been convinced the results could be groundbreaking enough for me to stress over it. However, with Merit Signature Lip Liner, I'm willing to admit that I was wrong—I just needed to find the right product.
Shop Merit Signature Lip Liner
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At Who What Wear UK, we know that beauty isn’t one-size-fits-all. Our editors have tested thousands of products over the years—spanning skincare, makeup, hair and nails—and work closely with trusted experts including dermatologists, makeup artists and leading industry insiders to ensure every guide is well-researched, inclusive and relevant to you.
We focus on formulas that deliver, whether they’re affordable favourites or luxury investments. Our product selection is based on tangible results, ingredient know-how and what we’d truly recommend to a friend.

Shannon Lawlor is the beauty director at Who What Wear UK. With over a decade of experience working for some of the beauty industry’s most esteemed titles, including Marie Claire, Glamour UK, Stylist and Refinery29, Shannon’s aim is to make the conversation around beauty as open, relatable and honest as possible. As a self-confessed lazy girl, Shannon has an affinity for hard-working perfumes, fool-proof makeup products and does-it-all skincare.