Are you applying your SPF every day — and, more importantly, are you using and applying it correctly? We all know that sun protection is integral to any good skincare regimen, but even the best sunscreen can't do its job if you're going wrong somewhere.

So, how do you know if you're wide of the mark? New York facialist Jillian Blair, owner of the recently-opened Jillian Blair Skin in London, has treated thousands of faces throughout her career, and says she can tell when mature clients aren't applying their sunscreen properly. ‘After 50, I can tell in seconds what someone hasn't been doing for their skin,’ she says.

Speaking with GH, the celebrity facialist reveals the five telltale signs your SPF isn't protecting your skin as effectively as it should — and what to do about it.

Signs your SPF isn't doing its job as well as it could

Your pigmentation is getting darker

Noticing sun spots in midlife? You're not alone. While SPF is (thankfully) trendy among younger generations, the same can't always be said for those now in their 40s, 50s and beyond, who weren't encouraged to wear suncream daily and are now seeing that exposure catching up.

Daily SPF helps prevent further damage, so if you’re still spotting new or worsening age spots, this suggests your sunscreen isn’t working for you as well as it could. 'New sun spots popping up out of nowhere is a sign of accumulated UV damage that your sunscreen wasn't blocking,’ says Jillian.

signs your spf isnt working
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Don’t ignore your pigmentation

Broken capillaries are appearing

Tiny red or purple veins appearing on your skin can be down to genetics, but they can be another sign that UV exposure is taking its toll.

signs your spf isnt working
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Don't ignore spider veins - these might be down to your SPF habits!

‘Redness or broken capillaries that weren't there before point to UV weakening the vessel walls over time,’ Jillian explains.

Fine lines are appearing sooner than expected

Fine lines are a natural part of ageing, but if they're appearing earlier than you'd expect, UV exposure could be speeding up the process.

signs your spf isnt working
PeopleImages
Premature ageing is a telltale sign your SPF isn't working as expected

As Jillian explains, ‘premature fine lines, and a general dullness in texture, are signs that UVA damage is breaking down collagen and slowing cell turnover, even without an obvious burn.’

Your skin tone looks uneven

Alongside a loss of radiance, uneven skin tone or rough texture can also point to cumulative UV damage. Jillian explains, ‘this is a sign that daily, incidental sun exposure has gone unprotected over time.’

You're still getting sunburnt

We've all been there. It can be incredibly frustrating to diligently apply SPF, only to end the day with sunburn. If you're still burning despite wearing SPF, it's a sign something isn't quite right with your application.

signs your spf isnt working
Eleganza
Wearing SPF and still getting burnt? Something isn’t right

Jillian warns, ‘if you’re noticing sunburn or peeling after minimal exposure, this means UVB rays are getting through and damaging the skin's outer layers.’ (Keep reading to find out why this could be.)

What can I do?

If you're already applying SPF every day but these telltale signs sound all too familiar, there are some key things to check.

Check how much you're using

Sun protection products are rigorously tested in the UK, but their effectiveness relies on you applying them in sufficient amounts. Bottom line: using too little will leave your skin under-protected. ‘Most people are applying less than half of what they need and skip reapplying every two hours, which means your SPF is probably only working at half its strength,’ says Jillian.

signs your spf isnt working
Ridofranz
Be generous with your application

To get the right dose of sun protection, Jillian says, 'My advice is always to apply a full, generous layer as your last skincare step every morning, which means around half a teaspoon for the face alone'. Be sure to use a high factor (SPF30+) sunscreen with broad spectrum UVA/B protection.

Jillian adds that you should never rely on makeup with built-in SPF – you always need a dedicated sunscreen. ‘You’re unlikely to apply SPF makeup thick enough to work,’ she says. ‘Remember that everyday exposure adds up too, so full protection matters even on days you're not deliberately in the sun.’

Check how often you're reapplying

Even the best sunscreen applied in the proper amount will break down when you're out in the sun. And that means it can't continue to protect your skin indefinitely. Reapplying every two hours is vital when you're want to guard against pigmentation popping up on sunny days.

Check the expiry date

If your application is diligent, but you still seem to fall victim to UV rays, be sure to check the expiry date. ‘Expired product is one of the most overlooked culprits,’ Jillian says.

You also want to consider how the product has been stored, which can shorten its useful life. Heat and UV are enemies to sunscreen, even in the bottle.

‘The active ingredients in SPF degrade over time, especially if the bottle's been sitting in a hot car,’ says Jillian.

If your sunscreen was sitting in a beach bag on last year's holiday, you'll definitely want to bin in.