How To Whiten Teeth At Home: A Beginner's Guide

Teeth whitening at home in the UK means one of two things: a whitening kit your dentist prescribes for you to use at home, or a product sold to the public that you apply yourself, such as whitening strips, a ready-made tray kit, a pen or an LED kit. To whiten your teeth at home, choose one of those and follow its directions for the whole course. Products sold over the counter may contain or release no more than 0.1% hydrogen peroxide, peroxide above that and up to 6% is sold only to dental practitioners, and only a registered dental professional may whiten your teeth for you. This guide covers how each method works, a 14-day routine with PAP strips, protecting the result, and when to see a dentist instead.

What is legal for teeth whitening at home in the UK

Products you buy and use on your own teeth come under cosmetics law. Annex III of the cosmetic products regulation, as it applies in Great Britain, allows oral products, "including mouth rinse, tooth paste and tooth whitening or bleaching products", to contain no more than 0.1% hydrogen peroxide, "present or released". That phrase means carbamide peroxide counts too, because it releases hydrogen peroxide. Tooth whitening products above 0.1% and up to 6% are "To be only sold to dental practitioners." For each cycle of use, the first use is by a dental practitioner, or under their direct supervision "if an equivalent level of safety is ensured", before the product is provided to you to complete the cycle, and these products are "Not to be used on a person under 18 years of age."

That cap is a rule about hydrogen peroxide. PAP, short for phthalimidoperoxycaproic acid, is not hydrogen peroxide and does not release it, so the 0.1% entry does not govern it. A PAP product is still a regulated cosmetic and still needs its safety assessment. The detail, and what it means for what you can buy, is in the UK whitening rules in full, so it is not repeated here.

The other half of the law is about who may whiten your teeth for you. Asked in its FAQ about a whitening appointment with a beautician, the General Dental Council (GDC), the dental regulator, answers: "No. The law says that only registered dentists, dental therapists, dental hygienists or clinical dental technicians working to the prescription of a dentist can legally and safely provide tooth whitening treatment." Asked about someone offering whitening by a method they call self-administered, the GDC says: "Handing an individual a tooth whitening tray and advising them on application, amongst other things, could constitute the giving of 'advice or attendance' and in those circumstances would be a criminal offence."

So at home, legally, you are choosing between a kit from your own dentist and a product on sale to the public that you apply yourself. Our guide to your teeth whitening options sets those routes next to in-chair whitening at a practice, with what professional whitening costs.

Picking a method: how each one works

Home whitening products broadly work in one of two ways. Either a product carries a whitening agent that acts on the coloured compounds in the tooth, or it works mainly by abrasion, scrubbing stain off the surface. For the first kind, what separates one format from another is how the agent is held against your teeth, and for how long. The comparison below is about mechanism, not brands.

A kit from your dentist

The NHS describes a dentist prescribing "a kit which contains a whitening gel and small trays which are made to closely fit around your teeth, like a mouthguard". You wear the trays at home "for around 2 to 6 weeks to gradually whiten your teeth". The Oral Health Foundation says treatment with trays from your dental team "usually takes 1 to 2 weeks". Because it is prescribed, your dentist sets the gel and the routine. The NHS also says: "Using a kit from a dentist, or having it done at a dental surgery, is the safest way to have teeth whitening."

Ready-made tray kits

A home kit sold to the public pairs a gel with a ready-made tray or mouthpiece rather than one made for your teeth. The gel is the active part, so the first thing to read on the box is what it contains: hydrogen peroxide or carbamide peroxide, held to the 0.1% limit, or a peroxide-free agent instead.

Whitening strips

A strip is a thin film coated with gel on the side that touches your teeth. Its job is contact: holding the whitening agent flat against the front of the teeth for the time on the pack. A strip only whitens where it touches, so fit matters, and so does whether it stays put. Peroxide strips sold to the public are held to the 0.1% limit. PAP strips use a different agent: PAP is peroxide free, and it still works on the coloured compounds inside the tooth, just by a gentler route than peroxide takes. Our page on PAP teeth whitening explained goes through the chemistry.

Pens and LED kits

A whitening pen carries a gel that you brush onto the front of the teeth, with no tray or strip over it. An LED kit pairs a whitening gel with a small light that you hold or wear against the teeth. In both, the whitening agent is the gel, and the 0.1% limit applies to any hydrogen peroxide in it. The lights the NHS and the Oral Health Foundation describe are used at a dental surgery; neither page assesses the lights sold with home kits. We look at the evidence on each format in whitening strips vs pens vs LED kits.

Whitening toothpaste and powders

The American Dental Association (ADA), a United States source, says "Whitening toothpastes primarily rely on abrasives for mechanical removal of extrinsic surface stains, though some contain low levels of peroxide to help lighten tooth color." In the UK, any peroxide in a toothpaste falls under the same 0.1% limit as other oral products. Abrasive powders, such as charcoal or baking soda, work by abrasion too: they lift stain sitting on the surface by scrubbing it rather than by acting on the coloured compounds chemically.

Four questions to ask of any product

• What is the active ingredient? Hydrogen or carbamide peroxide, with no more than 0.1% hydrogen peroxide present or released, or a peroxide-free agent such as PAP. If you would rather avoid peroxide altogether, we have a page on non-peroxide whitening strips.
• How is it held against the teeth? A tray, a film, a painted layer or nothing at all.
• What is the course? How long each application lasts, how many days, and what happens after.
• What does the box say about who should not use it? Read the warnings before the first use, not after.

A 14-day routine for whitening at home with PAP strips

This is the routine for our own strips, taken from the box directions and our usage facts. Other products have their own directions, and theirs are the ones to follow. Pure Glow makes dry-fit teeth whitening strips with a no-slip grip, 28 strips to a box: a 14-day course of one treatment a day, upper and lower. If you are working towards a big day, our guide to teeth whitening before your wedding helps you time the course.

Before day 1: find your starting shade

The box includes a shade guide. Before your first strip, hold it up to your front teeth and note the shade you start from, because "up to 6 shades whiter in 14 days" is a ceiling that depends on where you start, not a promise. Our guide on how to find your starting shade explains how a shade is counted. Read the warnings on the box too, and if any of them applies to you, see the dentist section below before you begin.

Every day, days 1 to 14

1. Brush your teeth, then take the strips out of the sachet.
2. Dry your teeth with a towel rather than a tissue. Our strips grip even on wet teeth, but drying is part of the box directions.
3. Apply the smaller strip to your lower teeth first, then the larger one to your upper teeth, and press firmly so it sits against each tooth.
4. Leave them on for a minimum of 30 minutes. Longer is fine and uses all the formula; our founder often wears his for 45 minutes to an hour.
5. Do not eat while they are on. A sip of water is fine, and so is swallowing saliva. Do not swallow the strips.
6. Remove them and rinse with water, as the box directs.
7. Then avoid coffee, tea, red wine and strongly coloured food for about an hour.

Any time of day suits. The strips come off clean, so a morning strip before work is fine. If you wear Invisalign or a retainer, you can use the strips, but not while the aligners or retainer are in. A sensitivity toothpaste such as Sensodyne is fine to use alongside them.

Partway through: patchiness

Stains lift at different rates, so your smile can look patchy partway through a course. Carry on with one treatment a day and it evens out. If irritation occurs, the box says to stop and let it settle, and to see a dentist if it persists. Our strips are peroxide free and clinically tested for zero sensitivity, and there is more on that on our page about whitening strips for sensitive teeth.

Day 14: check against your starting shade

After the fourteenth day, hold the shade guide up to the same teeth and compare it with the shade you noted before day 1. That is the clearest way to measure your progress. The whole fortnight, with a plan to tick off each day and a section on keeping the result, is also in our free teeth whitening guide.

Protecting your result

Whitening at home is not a one-off. On how long whitening lasts, the Oral Health Foundation says: "Smoking and drinks like tea, coffee and red wine can cause staining to return more quickly. Good brushing and regular dental cleaning help maintain the result."

With our strips, our own usage facts add three things:

• The hour after each strip. Keep coffee, tea, red wine and strongly coloured food back for about an hour after you take a strip off, during the course and during top-ups.
• Top-ups. After the 14-day course, 2 to 3 strips a week is how our strips are designed to hold a shade.
• Your toothpaste. Our own advice is a mild, non-abrasive toothpaste.

If you have crowns, veneers, fillings or bonding at the front, plan for how they will look next to your natural teeth. Our strips cannot change the base colour of a crown, veneer, filling or bonding, but they can lift staining that has built up on top of it, so a restoration that matched before can stand out afterwards. We cover that in detail in whitening with crowns or veneers.

When to see a dentist

The Oral Health Foundation's whitening page ends: "Always speak to your dental team before whitening your teeth. They can make sure it is safe for you and help you choose the best option." Our box and the NHS also name specific situations.

Before you start

• If a box warning applies to you. Our box says not to use the strips with gum disease, ulcers, exposed gums or recent oral surgery, and to check the ingredients for allergies.
• If you have dental work at the front, or any concern about your dental health.
• If you are pregnant or breastfeeding. There is no safety data for using our strips in pregnancy or while breastfeeding, so check with your dentist or midwife first.
• For children. Our strips are not suitable for children under 12, as the box says.

Signs that are not a whitening job

Whitening is for colour, not for dental problems. On its tooth decay page, the NHS lists "white, brown or black spots on your tooth" among the signs you may have if a hole has formed in a tooth, and says to see a dentist if "you have problems with your teeth like toothache or a sharp pain in your tooth when eating or drinking" or if "your gums are painful, swollen, or bleed when you brush your teeth". It also says to have regular check-ups even if you do not have any problems. Our guide on how to remove stains from teeth sorts the stains you can lift at home from the ones a dentist should look at.

During and after a course

If irritation from the strips persists once you stop, the box says to see a dentist. If you would rather a dental professional did the whitening, the GDC says your dentist can "outline the costs and risks of the treatment".

Frequently asked questions

Is at home teeth whitening legal in the UK?
Yes, within limits. Products sold to the public may contain or release no more than 0.1% hydrogen peroxide, peroxide above that and up to 6% is only sold to dental practitioners, and only a registered dental professional may whiten your teeth for you. PAP is not hydrogen peroxide and does not release it, so the 0.1% entry does not govern it, though it is still a regulated cosmetic.

Is teeth bleaching at home the same as teeth whitening?
In UK law, yes. The regulation lists "tooth whitening or bleaching products" as one category, and the 0.1% hydrogen peroxide limit applies whichever word is on the box.

How long does it take to whiten teeth at home?
Our strips are a 14-day course, one treatment a day, designed to take you up to 6 shades whiter in 14 days, depending on where you start. For a kit from a dentist, the NHS gives around 2 to 6 weeks and the Oral Health Foundation usually 1 to 2 weeks.

Can I whiten my teeth at home if I have crowns or veneers?
Your natural teeth can whiten, but our strips cannot change the base colour of a crown, veneer, filling or bonding, though they can lift staining that has built up on top of it. Speak to your dentist first if the dental work is at the front.

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Related reading:

• How to use whitening strips
• How to choose whitening strips
• How often to use whitening strips
• Natural teeth whitening

Sources:

• Regulation (EC) No 1223/2009 on cosmetic products, Annex III, entry 12, as it applies in Great Britain. For the hydrogen peroxide limits.
• American Dental Association, Oral Health Topics: Whitening, last updated 16 August 2022. A United States source, for whitening toothpastes.
• General Dental Council, Tooth whitening and illegal practice, page undated. For who may whiten your teeth, self-administered methods and costs and risks.
• NHS, Teeth whitening, page last reviewed 19 August 2025. For the dentist's kit, its timing, the safest way and the dental surgery route.
• NHS, Tooth decay, page last reviewed 13 August 2025. For the signs of a hole forming and when to see a dentist.
• Oral Health Foundation, Tooth whitening, last reviewed 17 April 2026. For trays from your dental team, keeping a result and speaking to your dental team first.