Mascara is the one makeup item that most of us - no matter how bleary eyed we are - wouldn't skip. One coat of the black stuff can take your lashes from zero to hero in seconds, but what about mascara primers?

Lash primers are designed to work like a really good pair of underwear, prepping your lashes for mascara, making them longer, blacker and more voluminous than ever. But do they really work, or is it just another makeup step we don't need?

In the quest for beauty answers, there's no product our Cosmopolitan Beauty Lab team won't try. From holographic hair mousse, to UV neon lipstick (the less said about that the better) and magnetic false eyelashes.

So who better than the Beauty Lab team to find out if mascara primers really do work. We picked four of the best lash primers and four of our most willing Cosmopolitan Editors to put them to the ultimate test... On camera.

Estée Lauder Lash Primer Plus

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Cosmopolitan UK

Buy now Feelunique.com, £21

mascara primerpinterest
Estée Lauder

L'Oréal Paris Lash Paradise Mascara Primer

mascara primerpinterest
Cosmopolitan UK

Buy now Feelunique.com, £11.99

mascara primerspinterest
L'Oréal

Clinique Lash Building Primer

mascara primerspinterest
Cosmopolitan UK

Buy now Feelunique.com, £15.50

mascara primerspinterest
Clinique

Givenchy Base Mascara Perfecto

mascara primerpinterest
Cosmopolitan UK

Buy now Feelunique.com, £25

mascara primerspinterest
Givenchy

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Headshot of Laura Capon
Laura Capon
Former Senior Fashion & Beauty Writer

Laura is a former writer for Cosmopolitan UK, covering everything beauty and fashion related and specialises in makeup, plus-size fashion and the world of YouTube. Her favourite pastime is reminding everyone of that one time she met Charlie Hunnam and Jason Momoa. Please don't ask to see the pictures...