Nic salt and freebase are two forms of nicotine used in e-liquid. Nic salts feel smoother at higher strengths, so they suit small pod kits at 10mg or 20mg. Freebase feels sharper on the throat as strength rises, so it's usually vaped at lower strengths in bigger, more powerful devices. In the UK both are capped at 20mg/ml, sold in bottles of no more than 10ml, and used in tanks or pods of no more than 2ml.
What freebase nicotine is
Freebase is the form of nicotine used in most e-liquids before nic salts came along. It's the nicotine on its own, without an acid added. At low strengths, such as 3mg or 6mg, it's mild. As you go higher, the throat hit gets noticeably harsher, which is why high-strength freebase isn't pleasant for many people.
Freebase goes well with sub-ohm devices: bigger kits with low-resistance coils that run at higher power and produce lots of vapour. The more vapour you inhale, the less nicotine you need per ml, so lower strengths make sense there.
What nic salts are
Nic salts are made by combining nicotine with an acid, which brings down the pH of the liquid. The practical effect is a smoother feel on the throat, even at 20mg. That's the main reason pod kits and the old disposables were built around them.
Nic salts suit low-power, mouth-to-lung (MTL) vaping with coils of around 1 ohm and above. In that kind of device you're producing a small amount of vapour per puff, so a higher strength makes sense.
Side by side
| Nic salt | Freebase | |
|---|---|---|
| Throat feel at high strength | Smooth | Harsh |
| Common UK strengths | 10mg, 20mg | 0mg to 18mg, often 3mg or 6mg |
| Best device type | Pod kits, MTL | Sub-ohm kits, direct-lung |
| Vapour volume | Small | Large |
| Typical bottle | 10ml | 10ml with nicotine, or larger 0mg shortfills |
The UK limits, and where they come from
The rules on nicotine strength and bottle size come from the Tobacco and Related Products Regulations 2016, regulation 36. They were brought in under the EU Tobacco Products Directive, often shortened to TPD, and are still part of UK law. Under regulation 36:
- Nicotine e-liquid presented for retail sale must not contain more than 20mg/ml of nicotine.
- A dedicated refill container of nicotine e-liquid must not hold more than 10ml.
- A tank, cartridge or disposable holding nicotine e-liquid must not hold more than 2ml.
- Refill containers and devices must be child-resistant and tamper-evident.
These limits apply to nic salt and freebase equally. That's why every pod in the UK tops out at 2ml and every bottle of nicotine e-liquid is 10ml or smaller.
What about shortfills?
The 10ml limit is for liquid that contains nicotine. Larger bottles, often 50ml or 100ml, are sold as nicotine-free "shortfills" with space left in the bottle. Some vapers add a 10ml nicotine shot to them. Shortfills are almost always freebase-style, high-VG liquids meant for sub-ohm devices, so they're not a good match for most pod kits.
Which one should you use?
Base it on your device first, then on how much nicotine you want.
Using a pod kit with an MTL coil? Nic salts are the natural fit. Our best pod vape guide covers kits built around them.
Using a bigger sub-ohm kit with a loose draw? Freebase at a low strength is the usual choice.
Moving off disposables? Most UK disposables used 20mg nic salt, so a 20mg nic salt in a pod kit will feel most familiar. See our disposable vape alternative guide.
Some people step down over time, going from 20mg to 10mg nic salt, and later to low-strength freebase in a different device. Refillable kits make that easier, since you can buy any strength in a bottle. Our refillable pod vape guide explains how.
A note on VG and PG
Strength isn't the only number on the label. E-liquids are a blend of vegetable glycerine (VG) and propylene glycol (PG). Most nic salts are around 50/50, which soaks easily into small MTL coils. Freebase shortfills are often 70% VG or more, which is thicker and suits bigger coils. Putting a thick high-VG liquid in a small pod coil is a common cause of dry hits, which we cover in the burnt taste guide.
Flavour doesn't depend on the nicotine type
You'll find almost every flavour as both nic salt and freebase. If you like cold, sweet fruit, something like iced triple mango works the same way whichever base it comes in. For clean menthol, there's cool mint. The flavour library lists them by family.
Questions people ask
Can I use nic salts in any vape?
Nic salts suit low-power, higher-resistance coils, which is what most pod kits use. In high-power sub-ohm devices, a 20mg nic salt will feel far too strong for most people.
Is 20mg the strongest e-liquid you can buy in the UK?
Yes. UK law caps nicotine e-liquid at 20mg/ml, whether it's nic salt or freebase.
Why are big bottles of e-liquid nicotine-free?
Nicotine e-liquid can only be sold in bottles of up to 10ml. Larger 'shortfill' bottles are sold without nicotine, and some people add a 10ml nicotine shot themselves.
