Choosing the right nicotine strength is one of the most important decisions you'll make when switching from cigarettes to vaping. Get it right, and you'll satisfy your cravings without returning to tobacco. Get it wrong, and you might find yourself reaching for a cigarette or experiencing unpleasant side effects from too much nicotine.
This guide explains how nicotine strengths work, which level suits your smoking habits, and how factors like your device type affect your choice.
In This Guide
- Understanding Nicotine Strength - What Do the Numbers Mean?
- What Nicotine Strength Should I Choose Based on My Smoking Habits?
- Freebase Nicotine vs Nicotine Salts. Which Should I Choose?
- How Your Device Affects Nicotine Strength Choice
- Signs Your Nicotine Strength Is Wrong
- Reducing Your Nicotine Strength Over Time
- Quick Reference Guide
- Important Safety Information
Understanding Nicotine Strength - What Do the Numbers Mean?
Nicotine strength in e-liquid is measured in milligrams per millilitre (mg/ml). This tells you how much nicotine is present in each millilitre of liquid. You'll sometimes see this expressed as a percentage instead, for example, 20mg/ml is the same as 2%.
Here's how common strengths convert between the two formats:
| mg/ml | Percentage |
|---|---|
| 3mg | 0.3% |
| 6mg | 0.6% |
| 10mg | 1.0% |
| 12mg | 1.2% |
| 18mg | 1.8% |
| 20mg | 2.0% |
In the UK, the maximum legal nicotine strength for e-liquids is 20mg/ml (2%). This limit is set by the Tobacco and Related Products Regulations (TRPR), which implements minimum standards for safety and quality. Any e-liquid sold in the UK above this strength has not been subjected to the appropriate quality and safety checks and should be avoided.
What Nicotine Strength Should I Choose Based on My Smoking Habits?
Your previous smoking habits are the best starting point for choosing a nicotine strength. The goal is to match your nicotine intake closely enough that you don't experience cravings or withdrawal symptoms while transitioning away from cigarettes.
Recommended Strengths by Smoking Level
Non-smokers or very occasional social smokers (0-2 cigarettes occasionally):
Consider 0mg (nicotine-free) or 3mg if you want minimal nicotine. If you've never been a regular smoker, there's no reason to start using nicotine products.
Light smokers (1-5 cigarettes per day):
A strength of 3mg to 6mg is typically suitable. This provides enough nicotine to take the edge off occasional cravings without overwhelming your system.
Moderate smokers (5-15 cigarettes per day):
Consider starting with 6mg to 12mg. If you're using a mouth-to-lung device with nicotine salts, 10mg nic salts often work well for this group.
Heavier smokers (15-20 cigarettes per day):
A strength of 12mg to 18mg freebase, or 18-20mg nicotine salts, typically provides adequate nicotine satisfaction. This level delivers a pronounced throat hit similar to cigarettes.
Very heavy smokers (20+ cigarettes per day):
Starting at 18mg to 20mg is often necessary. At this level, nicotine salts are generally recommended as they deliver higher concentrations more smoothly than freebase nicotine.
The NHS advises that finding the right strength may take some experimentation, and that's completely normal. You should use your vape as much as you need to manage your cravings and withdrawal symptoms and not worry if you're vaping more than you used to smoke, particularly in the early days.
Freebase Nicotine vs Nicotine Salts. Which Should I Choose?
There are two main types of nicotine used in e-liquids, and understanding the difference helps you choose the right strength.
Freebase Nicotine
This is the traditional form of nicotine found in most e-liquids. It has a higher pH level (around 9), which produces a stronger throat hit particularly at higher concentrations. Many vapers who previously smoked appreciate this sensation as it more closely mimics the feel of a cigarette.
However, freebase nicotine becomes harsh to inhale at strengths above 12-18mg, which is why high-strength freebase liquids have become less common.
Best for:
- Sub-ohm and direct-to-lung (DTL) vaping at lower strengths (3-6mg)
- Vapers who prefer a pronounced throat hit
- More experienced vapers using higher-powered devices
Nicotine Salts
Nicotine salts use benzoic acid to lower the pH, making the vapour much smoother to inhale even at high nicotine concentrations like 20mg. They're also absorbed into the bloodstream more quickly, providing faster satisfaction similar to the experience of smoking a cigarette.
Best for:
- Mouth-to-lung (MTL) devices and pod systems
- New vapers transitioning from smoking
- Anyone who wants higher nicotine without the harsh throat hit
- Heavy smokers who need strong nicotine to manage cravings
If you're just starting your vaping journey after being a regular smoker, nicotine salts in a simple pod device are often the easiest path to success.
How Your Device Affects Nicotine Strength Choice
The type of vape device you use significantly impacts how much nicotine you consume per puff—which means the ideal strength varies depending on your hardware.
Mouth-to-Lung (MTL) Devices
These include most pod systems, starter kits, and devices with tight airflow. You draw vapour into your mouth first, then inhale into your lungs—similar to smoking a cigarette. MTL devices produce less vapour and work best with higher nicotine strengths.
Recommended strengths: 10mg-20mg nicotine salts, or 12mg-18mg freebase
Direct-to-Lung (DTL) / Sub-Ohm Devices
These use low-resistance coils (below 1 ohm) and produce large amounts of vapour. You inhale directly into your lungs without holding the vapour in your mouth first. Because you're consuming significantly more vapour per puff, you need a much lower nicotine strength.
Recommended strengths: 3mg-6mg freebase
Pod Systems with Replaceable Coils
Many modern pod devices offer coils in different resistances. Check your coil resistance:
- Above 1.0 ohm: Use as MTL with 10-20mg nicotine salts
- 0.5-1.0 ohm: A middle ground; 6-10mg works well
- Below 0.5 ohm: Use lower strengths as you would with sub-ohm devices
Signs Your Nicotine Strength Is Wrong
Getting your nicotine strength right might require some adjustment. Here's how to tell if you need to change:
Signs Your Strength Is Too High
If you experience any of the following, particularly early in your vaping journey, your nicotine strength may be too high:
- Dizziness or lightheadedness
- Headaches
- Nausea
- Racing heartbeat
- Feeling jittery or anxious
These symptoms typically pass quickly if you stop vaping and wait. If you regularly experience these effects, move down to a lower nicotine strength. According to Cleveland Clinic, these are common symptoms of consuming more nicotine than your body is comfortable with.
Signs Your Strength Is Too Low
- You're vaping constantly but still feeling unsatisfied
- You're experiencing cravings for cigarettes
- You're thinking about smoking again
- You're going through e-liquid very quickly
If this describes your experience, try a higher nicotine strength. The NHS emphasises that the most important thing is staying off cigarettes—if a higher nicotine strength helps you do that, it's the right choice for now.
Reducing Your Nicotine Strength Over Time
One of vaping's advantages over cigarettes is the ability to gradually reduce your nicotine intake. Many vapers start at a higher strength and work down over months or years.
There's no pressure to reduce - NICE (the National Institute for Health and Care Excellence) recommends that people should use vapes for as long as they help prevent returning to smoking. However, if you'd like to reduce, here's a sensible approach:
- Wait until you feel stable and comfortable at your current strength
- Drop by one level (e.g., 20mg to 18mg, or 6mg to 3mg)
- Give yourself at least 2-4 weeks to adjust before considering another reduction
- If cravings return or you find yourself vaping excessively, it's fine to move back up
Some vapers eventually reach 0mg and continue vaping for the habit and flavour alone, while others maintain a low nicotine level indefinitely. Both approaches are valid.
Quick Reference: Choosing Your Starting Strength
| Your Smoking Habit | Recommended Strength | E-Liquid Type |
|---|---|---|
| Never smoked / social only | 0mg or don't start | Either |
| 1-5 cigarettes/day | 3-6mg | Freebase or low nic salt |
| 5-15 cigarettes/day | 6-12mg freebase or 10mg nic salt | Either |
| 15-20 cigarettes/day | 12-18mg freebase or 20mg nic salt | Nic salts recommended |
| 20+ cigarettes/day | 18-20mg nic salt | Nicotine salts |
Use these strengths for MTL devices, but reduce to 3-6mg if using sub-ohm equipment.
Important Safety Information
Store e-liquids safely: Nicotine is toxic if ingested, particularly for children and pets. Always keep e-liquids in child-resistant packaging and store them out of reach.
Pregnancy: The NHS advises avoiding all nicotine products during pregnancy due to potential effects on foetal development. If you're pregnant or planning to become pregnant, speak with your GP or midwife about stop smoking support.
Seek advice: Local Stop Smoking Services can provide free support and advice on choosing appropriate nicotine strengths. According to NHS guidance, combining a vape with expert support gives you the best chance of quitting smoking successfully.
Finding What Works for You
The "right" nicotine strength is simply the one that keeps you away from cigarettes while being comfortable to use. Evidence reviewed by Public Health England found that vaping is substantially less harmful than smoking, and the NHS recommends vaping as an effective stop smoking tool.
Start with the recommendations above based on your smoking habits, pay attention to how your body responds, and don't hesitate to adjust. It may take some experimentation with different strengths and devices to find your perfect setup—but that flexibility is one of vaping's greatest advantages over cigarettes.