The EU Tobacco Products Directive (2014/40/EU) — the TPD — controls how nicotine-containing e-liquid can be sold in the European Union. Article 20 is the part that governs the physical bottle. If you sell e-liquid in any EU market, this is the rule your packaging has to survive.
Refill containers for nicotine e-liquid may not exceed 10 millilitres. Cartridges and single-use pods may not exceed 2 millilitres. Bottles must be child- and tamper-proof, protected against breakage and leakage, and equipped with a mechanism that ensures refilling without leakage.
The Directive does not name a specific standard for child-resistance, but the industry has effectively standardised on EN ISO 8317 — the same reclosable-CR standard used for pharmaceuticals.
A 10ml maximum capacity — measured to the fill line, not the total bottle volume. A child-resistant closure that has been tested and documented against EN ISO 8317. A tamper-evident seal ring that visibly breaks on first opening. A dispensing mechanism (typically a fine-tip nozzle) that pours without leaking around the thread.
The Chubby Gorilla Unicorn v3 10ml is engineered against exactly this specification. That is why it is the default e-liquid bottle across the EU market.
TPD Article 20 also requires each e-liquid recipe to be notified to the national authority six months before it goes on sale in a market (through the EU-CEG database). That is a product-level compliance step, not a packaging one. The packaging rules apply regardless of whether the recipe is notified — a compliant recipe in a non-compliant bottle still cannot be legally sold.
TPD Article 20 covers e-liquid containing nicotine. Nicotine-free (0 mg) e-liquid falls outside Article 20 but many member states apply parallel national rules — most of which mirror the 10ml / CR / tamper-evident requirements anyway.
10ml is the maximum. You can sell 5ml or 7ml refill containers under the TPD framework. You cannot sell 15ml or 30ml refill containers of nicotine e-liquid in an EU consumer market.
Short-fill bottles contain 0mg nicotine base liquid and are technically outside Article 20's refill-container definition. They still have to meet general product-safety and CLP labelling rules. The workaround has been widely used across the EU but sits in a grey zone — check your national regulator's current position before designing around it.