When people ask “what’s inside a vape ”, they’re really asking about the liquid that creates the vapour, known as vape juice or e-liquid. This liquid is the heart of every device, whether it’s a pod kit, vape pen, or advanced mod, and it’s what delivers the flavour and nicotine that makes vaping enjoyable.

Understanding what’s in e-liquids is important for every vaper in the UK. Not only does it help you choose the right product for your needs, but it also ensures you’re aware of health, safety, and legal regulations. Unlike smoking, where the contents of a cigarette are hidden, vape juice ingredients are much more transparent and carefully controlled.

In fact, all e-liquids sold in the UK are strictly regulated under the Tobacco Products Directive (TPD) and monitored by the MHRA (Medicines & Healthcare Products Regulatory Agency). This means every bottle of vape juice has to be tested, reported, and kept within legal limits for things like nicotine strength and bottle size.

With the UK disposable vape ban in June 2025, more people are now moving to refillable kits and prefilled pods. This shift has made it even more important to know exactly what’s inside your e-liquid — from the base ingredients like PG and VG, to nicotine options, and the flavour concentrates that make vaping enjoyable.

This guide will give you a clear and simple explanation of vape juice, breaking down its main ingredients, safety, and the regulations that protect UK vapers.

What’s Inside a Vape?

The Core Ingredients of Vape Juice

At its core, every vape juice (also called e-liquid) contains a few main ingredients: Propylene Glycol (PG), Vegetable Glycerin (VG), Nicotine, and Food-Grade Flavourings. These ingredients are carefully balanced to give vapers the right mix of flavour, vapour, and throat hit. All of them are approved for use in the UK under TPD and MHRA safety standards.

Propylene Glycol (PG)

Propylene Glycol (PG) is a thin, clear liquid that’s also widely used in food, drinks, and medicine (like asthma inhalers).

• Role in vape juice: PG acts as the flavour carrier, making sure you taste the e-liquid properly. It also provides the “throat hit” that many ex-smokers like, because it feels similar to smoking a cigarette.

• Safety in the UK: PG is approved by the MHRA and has been considered safe for inhalation in regulated amounts.

Vegetable Glycerin (VG)

Vegetable Glycerin (VG) is a thicker, plant-based liquid often made from soy or palm oil. It’s sweet in taste and commonly used in food and cosmetics.

• Role in vape juice: VG is what produces the vapour clouds when you inhale. The higher the VG level, the smoother the vape feels, and the bigger the clouds.

• PG/VG ratio: Many UK e-liquids come in 50/50 mixes (good balance of throat hit and vapour) or 70/30 VG-heavy blends (popular with sub-ohm vapers and cloud chasers).

Nicotine (Freebase vs Nic Salt)

Nicotine is the addictive substance that helps smokers switch to vaping more easily. In the UK, nicotine in e-liquids is limited to 20mg per ml under TPD regulations.

• Freebase Nicotine: The traditional form of nicotine. It gives a stronger throat hit but can feel harsh at high strengths. Works well in vape pens and box mods.

• Nicotine Salts (Nic Salts): A newer form, designed to be smoother and faster-absorbing. Nic salts are popular in prefilled pod kits and disposables, because they give a strong nicotine hit without the harshness.

Flavourings

The final key ingredient is food-grade flavour concentrates, which make vaping enjoyable and help ex-smokers stay away from cigarettes.

• These are the same safe flavourings used in sweets, drinks, and baked goods.

• The UK market is especially popular for fruity, menthol, and dessert flavours, with top sellers being blue razz, grape, watermelon, and mango ice.

• Flavour variety is one of the biggest reasons vaping has become so popular in the UK, especially after the rise of disposables and now their replacement with pod kits.

Nicotine Strengths in the UK

One of the most important things to understand when choosing a vape is nicotine strength. In the UK, all e-liquids are regulated under the Tobacco Products Directive (TPD), which means the maximum nicotine strength allowed is 20mg/ml. This law ensures vapers have access to enough nicotine to quit smoking, but without the unsafe high levels found in unregulated markets.

0mg (Nicotine-Free)

• Best for vapers who enjoy the flavours and hand-to-mouth habit but don’t need nicotine.

• Often chosen by people who have already weaned themselves off nicotine but still like the vaping experience.

3mg – 6mg (Low Strength)

• Ideal for light smokers or beginner vapers using sub-ohm devices with lots of vapour.

• Provides a mild nicotine hit without being overwhelming.

10mg – 12mg (Medium Strength)

• Common choice for average smokers switching to vaping.

• Works well in refillable pods and vape pens.

18mg – 20mg (High Strength, TPD Max)

• Closest feel to smoking a cigarette.

• Popular in nicotine salts and prefilled pods because they deliver a smooth but strong hit.

• A great option for heavy smokers making the switch, especially after the UK disposable vape ban 2025, since pod kits now provide the same strong nicotine satisfaction.

Types of E-Liquids in the UK (Freebase, Nic Salts & Shortfills)

With the UK disposable vape ban in June 2025, more people are turning to refillable kits and prefilled pods. This has made it important to understand the different types of e-liquids available in the UK market. Each type offers a different experience, depending on your device and nicotine needs.

Freebase Nicotine E-Liquids

• The traditional form of vape juice, available for many years.

• Gives a stronger throat hit, which feels more like smoking.

• Works best in vape pens and box mods that produce more vapour.

• Available in lower strengths (3mg, 6mg, 12mg).

Nicotine Salts (Nic Salts)

• Designed to deliver nicotine more smoothly and quickly.

• Popular in pod systems like Hayati Pro Ultra, Geekbar Pods, and Fumot Pod Kits.

• Stronger nicotine strengths available in the UK (up to 20mg TPD limit).

• Perfect for ex-disposable users who want the same strong nicotine hit without the harshness.

Shortfill E-Liquids (For Sub-Ohm Vaping)

• Larger bottles of 0mg nicotine e-liquid (commonly 50ml or 100ml).

• Designed so vapers can add a nicotine shot (10ml booster) if needed.

• Popular with cloud chasers and those who prefer lower nicotine strengths.

• Usually made in high VG ratios (70/30) for big vapour production.

Key takeaway:

• Ex-disposable users → best option is nic salts in pod kits.

• New vapers → try freebase nicotine in simple vape pens.

• Advanced hobbyists → go for shortfills with box mods.

Are There Harmful Chemicals in Vapes?

One of the most common worries for new vapers in the UK is: “Do vapes contain harmful chemicals?” Some even believe in myths like “vape juice has antifreeze”. Let’s clear this up with facts.

Myth: Do Vapes Contain Antifreeze?

This myth comes from the ingredient Propylene Glycol (PG). PG is also used in products like food flavourings, medicines, and even asthma inhalers. Because PG can also act as a safe antifreeze in certain products, people wrongly assume that e-liquids are filled with harmful antifreeze chemicals.

The truth: The PG used in UK vape juice is pharmaceutical or food grade and completely safe for vaping under MHRA regulation. It is not the same as the antifreeze chemical (ethylene glycol), which is toxic and not allowed in e-liquids.

UK Regulation Keeps Vaping Safer

All vape juices sold in the UK must pass through MHRA (Medicines and Healthcare products Regulatory Agency) checks before they reach the market. This means:

• No dangerous chemicals like diacetyl (linked to popcorn lung) are allowed.

• Maximum nicotine strength is capped at 20mg/ml.

• Every product must be tested, reported, and listed on the MHRA website before sale.

This makes the UK one of the strictest and safest vape markets in the world.

Trace Chemicals vs Smoking

Yes, vape aerosol can contain trace chemicals (like tiny amounts of formaldehyde or acetaldehyde when e-liquids are overheated). But studies show that the levels are hundreds of times lower than in cigarette smoke.

• Cigarettes contain over 7,000 harmful chemicals, including tar and carbon monoxide.

• Vaping, by contrast, eliminates combustion and avoids most of those dangerous substances.

Public Health England Study

The most trusted research in the UK comes from Public Health England (now OHID), which found that:

“Vaping is at least 95% less harmful than smoking.”

This study is the basis of the NHS advice, which encourages smokers to switch to vaping as a safer alternative.

While no vape is 100% free of chemicals, UK-regulated e-liquids contain far fewer and much safer ingredients compared to cigarettes. The strict oversight of the MHRA ensures that what you’re inhaling is heavily tested and controlled.

UK Regulations on E-liquids (2025 Update)

The UK has some of the strictest vaping laws in the world, designed to keep e-liquids safe and regulated for consumers. All rules are based on the Tobacco and Related Products Regulations (TRPR), which follow the EU Tobacco Products Directive (TPD) — even after Brexit. These regulations are enforced by the MHRA (Medicines and Healthcare products Regulatory Agency).

Here’s what every UK vaper should know in 2025:

Maximum Bottle Size

• Any nicotine-containing e-liquid can only be sold in bottles of 10ml or less.

• This rule helps prevent accidental poisoning and ensures safe handling.

• Larger bottles, known as shortfills, can only be sold without nicotine (users can add nicotine shots separately).

Nicotine Strength Limit

• The maximum nicotine strength allowed in the UK is 20mg/ml.

• This applies to both freebase nicotine and nicotine salts.

• Many disposable vapes and pod kits use the 20mg strength because it delivers a strong but smooth hit.

Tank & Pod Capacity

• All tanks and refillable pods in the UK are limited to a maximum of 2ml capacity.

• This applies to pod kits, refillable vape pens, and mods.

• It means you’ll need to refill more often, but it also keeps devices within safe legal standards.

Ingredient Testing & MHRA Approval

• Every e-liquid sold in the UK must be submitted to the MHRA before it hits the market.

• The manufacturer has to provide a full list of ingredients, lab test results, and toxicology reports.

• Banned ingredients like diacetyl are not allowed in UK e-liquids.

Key takeaway: In the UK, all e-liquids are tightly controlled and regulated. Whether you’re using a prefilled pod kit, refillable pen, or shortfill, you can be confident that it meets TPD and MHRA standards in 2025.

Choosing the Right E-Liquid for You

With so many e-liquids available in the UK, it can be confusing to know which one will suit you best. The right choice depends on three main factors: nicotine strength, PG/VG ratio, and your device type.

Nicotine Strength Guide

Picking the correct nicotine strength is essential for both satisfaction and safety.

• 0mg: For vapers who enjoy the flavours and clouds but don’t need nicotine.

• 3mg – 6mg (Low): Great for light smokers or sub-ohm users who inhale more vapour.

• 10mg – 12mg (Medium): A balanced choice for average smokers moving to refillable kits.

• 18mg – 20mg (High): Strong nicotine hit, closest to a cigarette. Works best in nicotine salt pod kits.

PG/VG Ratio Guide

E-liquids in the UK come in different PG/VG mixes, which change the vaping experience.

• 50/50 Blends: Equal mix of propylene glycol (PG) and vegetable glycerin (VG). Balanced flavour, throat hit, and vapour. Best for pods and vape pens.

• 70/30 VG-Heavy: Produces smoother inhales and bigger vapour clouds. Works well in sub-ohm mods and advanced devices.

• High PG (60/40 or higher): Sharper throat hit and stronger flavour. Suitable for people who want a cigarette-like feel.

Match with Device Type

• Pod Systems: Best with nic salts or 50/50 e-liquids. This gives a smooth inhale with a strong nicotine hit, ideal for ex-disposable users.

• Vape Pens: Work best with balanced 50/50 blends, offering good flavour and moderate vapour.

• Box Mods / Sub-Ohm Kits: Designed for 70/30 high VG e-liquids, perfect for cloud chasing and lower nicotine levels.

Key takeaway:
If you’re new to vaping in the UK (especially after the disposable ban 2025), start with a prefilled pod kit or refillable pod using nicotine salts at 10mg–20mg. For hobbyists, mods with shortfills and 70/30 blends give the best cloud and flavour experience.

FAQs About Vape Juice

Here are some of the most common questions UK vapers ask about e-liquids in 2025:

What’s the safest vape juice?

In the UK, the safest e-liquids are those that are MHRA-approved and comply with TPD rules. Always buy from trusted vape shops and recognised brands. Popular regulated options include:

• Hayati Pods

• Geekbar E-liquids

• Fumot Vape Juices

Avoid buying unbranded or imported liquids that aren’t listed on the MHRA website.

 Can I mix my own e-liquids in the UK?

Yes, many advanced vapers make their own e-liquids using DIY vape kits. However, you must only use UK-regulated ingredients (PG, VG, nicotine shots, flavour concentrates). Keep in mind:

• Max nicotine strength is 20mg/ml.

• If selling to others, you’d need MHRA approval.

How long does 10ml e-liquid last?

It depends on your device and vaping style:

• Light vapers: 10ml can last 5–7 days.

• Moderate vapers: usually 3–4 days.

• Heavy vapers / pod users: sometimes only 1–2 days.

A disposable vape used to contain about 2ml of liquid, so a 10ml bottle = 5 disposables worth of e-liquid.

Do vape juices expire?

Yes. Most e-liquids in the UK have a shelf life of 1–2 years, clearly marked with an expiry or best-before date. After expiry:

• Flavours can fade.

• Nicotine strength may weaken.

• PG/VG can separate.

Always store e-liquids in a cool, dark place away from direct sunlight.

Are all e-liquids legal in the UK?

No. Only e-liquids that are submitted and approved by the MHRA can be sold legally in the UK. This ensures they meet safety standards such as:

• Max 20mg nicotine strength.

• No banned chemicals (like diacetyl).

• Bottle size limited to 10ml (if containing nicotine).

If you buy from a reputable vape shop in the UK, you can be sure your e-liquid is legal and safe.