Shortfills are the best-value way to buy e-liquid, but the first time you open one, the empty space in the bottle can be puzzling. This step-by-step guide shows how to mix a shortfill with nic shots, what strength you will end up with, and how to do it safely. Vaping is for adults and is best suited to people who already smoke or use nicotine.
Why Shortfills Have Empty Space
UK rules limit bottles of nicotine e-liquid to 10ml, but nicotine-free e-liquid can be sold in larger bottles. A “100ml shortfill” is a 0mg e-liquid supplied in a 120ml bottle. The extra 20ml of space is there so you can add nicotine shots, which are 10ml bottles of high-strength nicotine in a VG/PG base. If you do not want nicotine, you can vape the shortfill as it is. For a wider comparison of formats, read nic salt vs freebase vs shortfill.
What You Need
- A 100ml shortfill, for example Zeus Juice Blue Raspberry, IVG Mango Peach or Nasty Juice Watermelon Ice.
- One or two nicotine shots (sold separately), usually 18mg/ml.
- A clean surface and paper towel in case of drips.
Step-by-Step Mixing Guide
- Shake the shortfill gently so that the liquid is evenly mixed.
- Open the cap and check the bottle has the headspace you expect.
- Add the nic shot. Squeeze the 10ml shot straight into the shortfill bottle. If you want a stronger mix, add a second shot.
- Close the cap firmly and make sure it is fully tightened.
- Shake well for about a minute so that the nicotine is spread through the liquid.
- Let it rest for a few hours if you can, then shake again before filling your tank.
What Strength Will You End Up With?
The final strength depends on how many 18mg shots you add to a 120ml bottle.
| Shots added | Total volume | Approx. strength |
|---|---|---|
| None | 100ml | 0mg |
| One 18mg shot | 110ml | about 1.6mg |
| Two 18mg shots | 120ml | about 3mg |
These figures are calculated by dividing the total nicotine by the total volume. A final strength of 3mg is typical for sub-ohm vaping and sits far below the UK limit of 20mg/ml. If you want a higher strength, consider a nic salt instead, and see our nicotine strength guide for help.
Which Device Should You Use?
Shortfills are usually high in VG and made for sub-ohm tanks, which produce larger clouds. They are generally too thick for small pod kits. If you use a pod kit, nic salt is the better choice, and our pod kit buyer’s guide explains why. Browse the shortfill category if you use a sub-ohm tank.
Tips and Common Mistakes
- Do not overfill. The extra headspace is only large enough for the stated number of shots.
- Label the bottle with the date and the number of shots you added.
- Shake before each use. The nicotine can settle slightly over time.
- Keep out of reach of children. Nicotine shots are concentrated, so store them carefully and wash your hands after handling.
Is Mixing Your Own E-Liquid Different?
Yes. Mixing a shortfill only adds nicotine to a ready-made flavour. DIY mixing builds the e-liquid from scratch, using flavour concentrates, a VG/PG base and optionally a nic shot. Our DIY concentrates, such as Dampflion Checkmate Rook’s Reserve, are only for experienced mixers and are never to be vaped undiluted.
Why Choose a Shortfill at All?
The main reason is value. A 100ml bottle usually costs much less per millilitre than ten separate 10ml bottles, so heavy vapers save money over time. Shortfills also give you control: you can leave a bottle nicotine-free, add one shot for a very light strength, or add two for a slightly stronger mix. That flexibility is why many sub-ohm users prefer them, and why nicotine-free vapers like the large, cost-effective bottles.
The trade-off is convenience. A 120ml bottle is bulky to carry, so many people refill a small travel bottle from the large one. Always label any decanted bottle with the flavour and strength, and keep it away from children. If you mostly vape on the move with a small device, a 10ml nic salt may suit you better than a shortfill.
Storing Your Mixed Bottle
Store the bottle upright in a cool, dark place. Heat and sunlight can change the colour and flavour of e-liquid over time. If you notice the colour darkening a little after adding nicotine, that is normal, but if the smell or taste changes sharply, it is safer to replace the bottle.
Frequently Asked Questions
Can I add more than two shots?
No. A 120ml bottle only has room for two 10ml shots. Overfilling can cause leaks.
Do I have to add nicotine?
No. A shortfill is supplied at 0mg and can be vaped as it is.
How long should I wait after mixing?
A few hours is fine, though you can vape straight after shaking well.
Explore the full e-liquid and shortfill range or visit the shop. You must be 18 or over to buy.
Related guides: DIY e-liquid concentrates guide and comparing the same nic salt flavour across brands.