Key takeaways
- A shortfill is a large bottle of 0mg vape juice deliberately under-filled (a 50ml juice in a 60ml bottle), leaving room to add nicotine.
- A nic shot is a small 10ml bottle of high-strength nicotine (usually 18mg or 20mg) you pour into the shortfill and shake.
- They exist because of UK/EU law: nicotine-containing e-liquid is capped at 10ml bottles and 20mg strength, so big bottles are sold as 0mg + separate shots you mix yourself.
- The mixing is easy: a 50ml shortfill plus one 18mg nic shot makes 60ml of roughly 3mg juice. Shake well, and it’s ready.
- US vapers rarely need them — without the 10ml cap, big pre-mixed nicotine bottles are sold directly.
What is a shortfill?
A shortfill is a bottle of nicotine-free (0mg) e-liquid sold in a larger bottle with space left at the top for you to add nicotine. The classic format is “50ml in a 60ml bottle” — 50ml of flavored 0mg juice, with a 10ml gap. That gap is the whole point: it’s where a nic shot goes. You’ll also see 100ml-in-120ml shortfills (room for two shots) and other sizes, always with the headroom built in.
Everything else about a shortfill is just normal vape juice — the same PG/VG base, flavor and (soon) nicotine as any bottle. It’s only sold this way to work around the rules, which is where nic shots come in.
What is a nic shot?
A nic shot is a small 10ml bottle of concentrated, unflavored nicotine — almost always 18mg or 20mg — that you add to a shortfill to bring it up to strength. It comes in freebase or nic-salt form; you pick to match the juice and device (nic salts for a smoother, pod-friendly hit; freebase suits bigger setups). One shot is the standard dose for a 50ml shortfill; a 100ml shortfill takes two. Most shots come in a 50:50 base, which barely nudges a shortfill’s ratio — but if you’re topping up a Max-VG shortfill and want to keep it thick for a sub-ohm tank, look for a high-VG nic shot to match.
Why do shortfills and nic shots exist?
It’s a legal workaround, and a neat one. Under the UK and EU Tobacco Products Directive (TPD), e-liquid that contains nicotine can only be sold in bottles up to 10ml, and at a maximum strength of 20mg/mL (2%). Selling a big 50ml or 100ml bottle of nicotine juice simply isn’t allowed.
The industry’s answer: sell the big bottle with zero nicotine (which isn’t restricted), plus a separate little 10ml nic shot (which fits the 10ml rule), and let the customer combine them at home. You get a big-bottle price and choice, you stay inside the law, and you control the final strength. It’s why shortfills dominate the UK refillable market.
US note: the US has no equivalent 10ml bottle cap, so American vapers usually just buy larger bottles pre-mixed with nicotine — shortfills and nic shots are mainly a UK/EU thing.
How to add a nic shot (and the math)
Mixing a shortfill takes about a minute:
- Open the shortfill and the nic shot.
- Pour the whole nic shot into the shortfill. One 10ml shot fills the 10ml gap in a 50ml/60ml shortfill exactly.
- Cap it and shake well for 30–60 seconds so the nicotine blends evenly.
- Vape it, or let it steep for a day or two if you want the flavor to settle.
The resulting strength is simple to work out: (shot strength × shot volume) ÷ total volume. So a 50ml shortfill plus one 18mg 10ml shot = 180mg of nicotine in 60ml = 3mg/mL. Here’s the quick reference:
| Shortfill | Nic shot(s) | Final volume | Final strength |
|---|---|---|---|
| 50ml (in 60ml) | 1 × 18mg | 60ml | 3mg |
| 50ml (in 60ml) | 1 × 20mg | 60ml | ~3.3mg |
| 100ml (in 120ml) | 2 × 18mg | 120ml | 3mg |
| 100ml (in 120ml) | 2 × 20mg | 120ml | ~3.3mg |
If you want a lower strength, add less than a full shot (and top up with plain 0mg base to keep the ratio). Most people just use the standard one-shot-per-50ml, which lands around 3mg — a common all-day strength for bigger devices (our nicotine strengths guide covers picking one).
Shortfills vs pre-mixed nicotine juice
- Shortfills win on choice and value: big bottles, huge flavor range, and you set the nicotine. Best for higher-VG, sub-ohm-style juice at lower strengths (which is what most shortfills are).
- Pre-mixed 10ml nicotine bottles win on convenience and high strength: no mixing, and they go up to 20mg, which suits small pods and heavier ex-smokers. This is where nic salts live.
If you’re on a small pod and want a strong hit, a ready-made 10ml nic-salt bottle is simpler. If you’re on a bigger device and want a big bottle of flavor at a low strength, a shortfill is the way — and we’ve tested the best vape juice flavors if you’re picking one. Our guide to choosing the right vape juice covers which suits you.
FAQ
What does “shortfill” mean?
It’s a bottle of 0mg vape juice deliberately under-filled — like 50ml of juice in a 60ml bottle, leaving room to add a 10ml nic shot. The “short” fill is the gap left for nicotine.
How many nic shots go in a shortfill?
One 10ml shot per 50ml of shortfill (so two for a 100ml). One 18mg shot in a 50ml/60ml shortfill gives you roughly 3mg.
What strength does a shortfill and one nic shot make?
A 50ml shortfill plus one 18mg 10ml nic shot makes 60ml at about 3mg/mL. Use a 20mg shot and it’s a touch higher, around 3.3mg.
Do I need to steep a shortfill after adding a nic shot?
Not strictly — shake it well and it’s ready to vape. A day or two of steeping can let the flavor settle, especially with richer juices, but it’s optional.
Do shortfills exist in the US?
Rarely. They’re a UK/EU solution to the 10ml nicotine-bottle limit. The US has no such cap, so American vapers typically buy larger nicotine bottles pre-mixed.
