Snow teeth whitening

Our verdict

We would not recommend Snow to UK buyers. The whitening ingredients are standard, but three things count against it here. Snow does not publish the strength of its serums. Its terms say its website and products are intended for sale and use in the United States. And its 30-day money-back guarantee applies to US purchasers only. Some UK online shops resell Snow kits, but that does not answer the strength question. If you want more than a whitening toothpaste can do, ask a dentist about take-home trays, which are the legal route in the UK for stronger products.

Which Snow product is which

Snow's range has changed since 2020: the photo on this page, from our 2020 review, shows an earlier corded kit. On 29 October 2026 Snow's website sold two main kits, each a three-pen pack plus an LED mouthpiece. Each kit is sold once or by subscription; on a subscription the mouthpiece comes only with the first order, and pen refills follow every one, two or three months until you skip, pause or cancel.

Older DiamondSeries kits, wired and wireless, are still listed by some UK resellers. Snow's own DiamondSeries page now shows the Sensitive kit. If you buy from a reseller, check which kit and serum you are getting.

What is in the serums

Both current pens list hydrogen peroxide and carbamide peroxide, which do the whitening, plus potassium nitrate, an ingredient used for sensitivity, and hydroxyapatite. Carbamide peroxide breaks down into hydrogen peroxide, so the strength that matters is the total hydrogen peroxide released. Snow does not publish that figure for any serum. Snow describes the Extra Strength pen as its strongest serum.

In the UK, tooth whitening products that contain or release up to 0.1% hydrogen peroxide can be sold to the public. Products above 0.1% and up to 6% may only be supplied through a dentist after an examination, with the first use under their supervision, and not to anyone under 18. Without a published strength we cannot say which group Snow's serums fall into.

When Which? tested 36 whitening products bought from online marketplaces in 2021, 21 contained more hydrogen peroxide than the legal limit for home use, which is why an unpublished strength matters.

What the evidence says about the serum

Peroxide whitening at home does work. A 2018 Cochrane review of 71 trials found that home bleaching products, including paint-on gels, whitened teeth more than placebo over periods of two weeks to six months, although the certainty of the evidence was low to very low. It could not say which product, strength or method is best. Two small head-to-head trials, from 2003 and 2007, found that paint-on peroxide gels whitened less than whitening strips. No independent trial of Snow's own serums has been published that we could find.

What the evidence says about the LED light

The light is a separate question. A 2019 network meta-analysis of 28 trials of dentist whitening found no light-activation system that improved the colour change, at high or low peroxide strengths. An earlier review found that light activation raised the risk of tooth sensitivity, with a possible short-term benefit only at 15 to 20% hydrogen peroxide, far above what is legal for home use in the UK. These trials used professional lights, not small battery or phone-powered mouthpieces, and we found no independent trials of home LED mouthpieces. Snow's FAQ gives its light as under 1 watt, blue at 460 to 462 nm and red at 620 to 625 nm, and claims red light kills bacteria and reduces inflammation; we have not seen evidence for that claim in a whitening device.

In short, the peroxide is the part of Snow with evidence that it whitens teeth. Trials of professional lights did not show a benefit, and we found no independent trial of Snow's mouthpiece, so whether its light adds anything is unknown rather than disproved.

Which instructions apply to which kit

Snow's website carries instructions for its current kits and for older ones, and most of the differences come from that. The overnight serum and the 9 to 30 minute LED session are separate steps, not competing timings. This matters in the UK because resellers still sell older kits.

For the current kits, two things are unclear. Snow's general FAQ answer on how often to whiten, which does not name a kit, says 9 to 30 minutes a day for 21 to 30 days, with a one to three day break if you get sensitivity, while the Extra Strength kit page says 21 days. And the Sensitive kit page does not say how many nights to use the Overnight pen or how often to do daytime LED sessions. Follow the leaflet that comes with your kit. If there is none, or you bought an older kit from a reseller, ask Snow for the instructions for that exact kit before you start. Stop and see a dentist if you get pain or sensitivity that does not settle.

On age, the kit pages say the pens are for ages 12 and over and the mouthpiece for adults; Snow's FAQ says its products are designed for adults and that 12 to 17 year olds should consult a dentist. In the UK, products above 0.1% hydrogen peroxide may not be supplied to anyone under 18; because Snow does not publish its strength, under-18s should ask a dentist before using it.

Buying from the UK

Snow lists the United Kingdom among the countries it ships to. Expect international delivery times and possibly import charges. Snow's 30-day money-back guarantee applies to purchasers in the United States only, and its terms say its products are intended for sale and use in the US, so UK buyers should not assume they can get a refund for a product that did not work. Snow says it handles returns only for orders from its own site, Indiegogo and Amazon; orders from other shops are handled by those shops. If you choose the subscription rather than a one-time purchase, note how to skip or cancel before your first refill is sent.

Electronics in the mouthpiece carry a 2-year warranty, according to Snow's FAQ.

During aligner treatment

Ask the dentist supervising your treatment before whitening. Tooth-coloured attachments bonded to your teeth for aligner treatment will not change colour, and Snow says the same about fillings, crowns and veneers, so you may want to wait until the attachments are removed.

Do not put Snow serum inside your aligners: they are not designed as whitening trays and the dose would be uncontrolled.

Some dentists do supply whitening gel for use in aligner-style trays, which is a different, supervised treatment. Our guide to whitening at home covers the UK options.

How this review was put together

This review first appeared on Aligners.co in August 2020, and the photo is from that review. The original repeated customer numbers and a satisfaction rating from Snow's website; those figures are Snow's own and have not been carried over. This update is based on Snow's current product pages, FAQs, guarantee and terms, UK regulations and guidance, two UK reseller listings, and published systematic reviews and trials, checked on 28 and 29 October 2026. We did not test Snow products, and the page has not been clinically reviewed.