The Core Ingredients

Every e-liquid, regardless of brand or flavour, is built from the same four basic components. It's the ratio and quality of these four elements that separates a good e-liquid from a mediocre one.

Freebase Nicotine vs Nic Salts

Nicotine in e-liquid comes in two distinct forms, and the difference between them changes how quickly you feel satisfied and how harsh or smooth the vape feels, independent of the flavour itself.

Freebase nicotine is the traditional form used in e-liquids since vaping began. It delivers a noticeably sharper throat hit at higher strengths, which is why freebase e-liquids are typically capped around 3mg to 18mg, since anything stronger becomes genuinely uncomfortable to inhale.

Nicotine salts, or nic salts, are chemically modified so the nicotine is absorbed into the bloodstream faster and with a noticeably smoother throat feel, even at higher strengths like 10mg or 20mg. This is exactly why nic salts have become the default choice for smokers switching to vaping, since they more closely replicate the fast nicotine delivery of a cigarette.

Choosing the Right Nicotine Strength

Getting your nicotine strength right matters more than most people realise. Too low, and you'll find yourself vaping constantly trying to chase a satisfaction that never quite arrives. Too high, and the hit becomes harsh enough to put you off vaping altogether.

• 0mg — No nicotine at all, chosen by vapers who enjoy the habit and flavour without any nicotine intake.
• 3mg to 6mg — Suited to light or social smokers, typically paired with higher-VG freebase e-liquids in sub-ohm devices.
• 10mg — A common nic salt strength for moderate smokers or vapers stepping down from 20mg.
• 20mg — The UK legal maximum, best suited to heavier smokers switching from cigarettes who need a stronger, faster hit.

If you're unsure where to start, our Vaping Knowledge hub covers this in more depth, and our customer support team can talk you through it based on your smoking history.

Storage, Shelf Life and Safety

E-liquid is fairly stable, but it isn't indefinite. Stored correctly, most bottles remain good for around 1 to 2 years from the manufacturing date, though flavour intensity can fade gradually over time even before the liquid technically expires.

• Keep bottles somewhere cool and dark, away from direct sunlight, which breaks down flavourings and nicotine faster than normal ageing.
• Always store upright with the cap fully closed to prevent slow evaporation and contamination.
• Keep all e-liquid, especially nicotine-containing bottles, well out of reach of children and pets. Nicotine is toxic in concentrated amounts.
• Discard any bottle that has changed colour dramatically, smells noticeably different, or has been open for more than a few months.

TPD Compliance Explained

Every e-liquid sold legally in the UK falls under the Tobacco Products Directive, commonly shortened to TPD. This regulation sets firm limits on what can be sold, and understanding it helps explain why UK e-liquid looks and works the way it does compared to products from other countries.

• Nicotine-containing e-liquid bottles are capped at 10ml in size.
• Nicotine strength cannot legally exceed 20mg per ml (2%).
• All bottles must include child-resistant caps and tamper-evident seals.
• Every product must display clear nicotine warnings and ingredient information.
• Ingredients and manufacturing must meet strict safety and quality notification requirements before sale.

Every nicotine e-liquid we stock at Ecosmok is fully TPD compliant, sourced through verified UK distribution channels rather than unregulated imports.