Nicotine Guide: Salts vs Freebase, Strengths, Shortfills & Device Matching
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Introduction
Choosing the right nicotine format and e-liquid blend can feel overwhelming, especially with so many options on UK shelves. This guide breaks down everything you need to know — from nicotine salt versus freebase to shortfills, nic shots, PG/VG ratios, and device compatibility — so you can make an informed choice and get the best experience from your vape.
Nicotine Salts vs Freebase Nicotine: What's the Difference?
Freebase Nicotine
Freebase is the traditional, "pure" form of nicotine used in most e-liquids. It has a higher pH, which means it can feel harsher on the throat at higher concentrations. This makes it well-suited to sub-ohm devices where lower strengths (3mg–6mg) are used with high wattage and high vapour volume.
- Available strengths: typically 3mg, 6mg (in shortfills after mixing)
- Best for: sub-ohm tanks, mesh coil devices, high-wattage mods
- Throat hit: more pronounced at higher mg
- Flavour: excellent at low strengths with high VG blends
Nicotine Salts
Nicotine salts use benzoic acid to lower the pH of nicotine, allowing higher strengths to be inhaled far more smoothly. They deliver nicotine to the bloodstream faster than freebase, making them especially popular with vapers transitioning from smoking.
- Available strengths: typically 5mg, 10mg, 20mg (UK legal maximum)
- Best for: pod kits, mouth-to-lung (MTL) devices, low-wattage vapes
- Throat hit: noticeably smoother than equivalent freebase strengths
- Nicotine satisfaction: faster and more pronounced per puff
Browse our range of Nicotine Salts & Nic Salt Boosters — available in a wide variety of flavours and strengths.
Which Should You Choose?
| Factor | Freebase | Nicotine Salts |
|---|---|---|
| Device type | Sub-ohm / high power | Pod / MTL / low power |
| Strength range | 3mg–6mg (post-mix) | 5mg–20mg |
| Throat hit | Stronger | Smoother |
| Nicotine speed | Slower absorption | Faster absorption |
| Best for | Cloud chasers, experienced vapers | Smokers switching, pod users |
Common Nicotine Strengths Explained
UK regulations (TPD/TRPR) cap nicotine-containing e-liquid at 20mg/ml in bottles up to 10ml. Here's a practical guide to the common strengths you'll encounter:
0mg (Nicotine-Free)
Zero nicotine. Found in shortfills before a nic shot is added. Also used by vapers who have successfully stepped down from nicotine but enjoy the ritual and flavour of vaping.
3mg
A low strength typically used in freebase e-liquids with sub-ohm devices. Suited to vapers who consume high volumes of vapour or those who have already reduced their nicotine intake significantly.
6mg
The standard result when adding one 18mg nicotine shot to a 50ml shortfill. Suitable for regular sub-ohm vapers who want a mild-to-moderate nicotine presence.
10mg
Available in both freebase and salt formats. Popular with MTL vapers on lower-powered devices and those making the transition from smoking with a moderate-to-high daily consumption.
20mg
The maximum legal strength in the UK. Almost exclusively nicotine salt format due to the smoothness required at this level. Ideal for heavier smokers making the switch, or those using very low-powered pod systems with restricted airflow.
Shortfills & Nicotine Shots: How the System Works
UK regulations prohibit selling nicotine-containing e-liquid in bottles larger than 10ml. Shortfills are the practical solution: a larger bottle (60ml, 100ml, 120ml) filled to 83–88% capacity with a 0mg e-liquid, leaving space to add a separate nicotine shot.
The Maths Made Simple
- 50ml shortfill + one 10ml 18mg nic shot = 60ml at 3mg
- 50ml shortfill + one 10ml 36mg nic shot = 60ml at 6mg
- 100ml shortfill + two 10ml 18mg nic shots = 120ml at 3mg
Most UK vapers use the 50ml + one 18mg shot combination to achieve a 60ml bottle at 3mg. If you prefer 6mg, simply use a higher-strength nic shot.
Nic Salt Boosters in Shortfills
You can also add nicotine salt boosters to shortfills if you want a smoother hit at your target strength. This is particularly useful for MTL vapers using shortfills rather than pod-format salts.
Shop our full range of Shortfill E-Liquids and stock up on Nicotine Shots & Nic Salt Boosters to complete the mix.
50/50 vs 70/30 Blends: PG & VG Explained
Every e-liquid is a blend of Propylene Glycol (PG) and Vegetable Glycerin (VG). The ratio significantly affects your vaping experience.
What is PG?
PG is a thin, odourless liquid that carries flavour efficiently and produces a noticeable throat hit. It is the dominant carrier in nicotine salt 10ml bottles and 50/50 e-liquids.
What is VG?
VG is a thicker, slightly sweet liquid responsible for vapour production. High-VG e-liquids produce dense clouds but require more power to vaporise effectively, which is why they are paired with sub-ohm coils.
50/50 (Equal Parts PG & VG)
- Thinner consistency — suitable for MTL devices and pod systems
- Stronger flavour and throat hit
- Less vapour production
- Works well at lower wattages (8–15W)
- Common format for nicotine salt 10ml bottles
Browse our 50/50 E-Liquids collection.
70/30 (70% VG, 30% PG)
- Thicker consistency — requires sub-ohm hardware to wick properly
- Larger, denser clouds
- Smoother inhale with less throat hit
- Best at higher wattages (30–80W+)
- The standard ratio for most shortfill e-liquids
Explore our 70/30 Shortfill E-Liquids collection.
Quick Comparison
| Feature | 50/50 | 70/30 |
|---|---|---|
| Vapour production | Low–moderate | High |
| Throat hit | Moderate–strong | Smooth |
| Flavour intensity | High | Moderate–high |
| Device requirement | Pod / MTL | Sub-ohm / high wattage |
| Typical nicotine format | Salts or freebase (10–20mg) | Freebase (3–6mg after mix) |
Matching Your Choice to Your Device
The most important rule in vaping: always match your e-liquid to your hardware. Using the wrong combination can lead to dry hits, coil flooding, or an unsatisfying nicotine experience.
Disposable Vapes
Disposables come pre-filled — you have no choice over e-liquid, so this section is more about understanding what's inside them. Most disposables use nicotine salt formulas at 20mg in a 50/50 or high-PG blend optimised for their internal coil.
Browse our Disposable Vapes range, including trending disposables.
Pod Kits & MTL Devices (8–20W)
- Recommended e-liquid: 50/50 blend or high-PG nicotine salts
- Recommended strength: 10mg–20mg
- Format: 10ml nic salt bottles
- Why: Low wattage means thin liquids wick best; high salt strength delivers satisfaction per puff without needing large vapour volume
MTL Sub-Ohm & Starter Kits (15–30W)
- Recommended e-liquid: 50/50 or 60/40 blends
- Recommended strength: 6mg–10mg freebase or 10mg salt
- Format: 10ml bottles or 50ml shortfill + nic shot
- Why: Moderate airflow and wattage suits thinner liquids and mid-range strengths
Sub-Ohm Tanks & High-Wattage Mods (40W+)
- Recommended e-liquid: 70/30 or max-VG shortfills
- Recommended strength: 3mg–6mg freebase only
- Format: 100ml shortfill + nicotine shots
- Why: High vapour output delivers nicotine efficiently at low concentrations; salts at 20mg on a sub-ohm device would deliver far too much nicotine per puff
Important: Never use high-strength nicotine salts (20mg) in a sub-ohm device. The volume of vapour produced means you would consume far more nicotine than intended.
Quick-Reference Summary
| Vaper Type | Device | E-Liquid Type | Strength | Blend |
|---|---|---|---|---|
| Smoker switching | Pod kit | Nicotine salt | 20mg | 50/50 |
| Casual MTL vaper | Pod / MTL kit | Nic salt or freebase | 10–20mg | 50/50 |
| Experienced MTL | MTL sub-ohm | Freebase | 6mg | 50/50–60/40 |
| Cloud / sub-ohm | Sub-ohm mod + tank | Freebase | 3–6mg | 70/30 shortfill |
| Nicotine-free | Any | 0mg shortfill | 0mg | 70/30 or 50/50 |
Frequently Asked Questions
Can I mix nicotine salts with a shortfill?
Yes. Nic salt boosters are designed specifically for this purpose. Adding a nic salt booster instead of a standard freebase nic shot gives you a smoother throat hit at the same strength — a popular choice for those who find freebase harsh.
Is 20mg too strong for me?
That depends on your device and your previous smoking habit. On a pod kit with restricted airflow, 20mg delivers a controlled amount of nicotine per puff comparable to what many smokers are used to. On a sub-ohm device, 20mg would be far too strong — stick to 3mg or 6mg on those devices.
What happens if I use a 70/30 shortfill in a pod kit?
High-VG liquids are too thick to wick efficiently in the small coils found in pod kits. This typically results in dry hits, burnt coils, and poor flavour. Always use a 50/50 blend in pod devices.
How do I know which blend is in my shortfill?
It will be stated on the label or product page. The vast majority of 100ml shortfills are 70/30; 60ml shortfills are commonly 70/30 or 60/40. Check before you buy if your device is lower-powered.
Shop by Category
- Nicotine Shots & Nic Salt Boosters
- Shortfill E-Liquids
- 100ml Shortfill E-Liquids
- 50/50 E-Liquids
- 70/30 Shortfill E-Liquids
- Disposable Vapes
This guide is intended for adults who are already using nicotine products and are looking to switch to or continue vaping. If you have questions about nicotine and your health, speak to a healthcare professional. You must be 18 or over to purchase vaping products in the UK.