Guide to Shortfill Liquids for UK Vapers

A 100ml bottle that is not quite full is not a packing mistake. That extra space is there for nicotine shots, and it is what makes shortfills a popular choice for UK vapers who want more liquid, more flavour options and better value per ml. This guide to shortfill liquids explains how they work, how to mix them and how to choose a blend that suits your kit.

What are shortfill liquids?

Shortfill e-liquids are larger bottles of nicotine-free vape juice with space left at the top. The bottle is deliberately filled short so you can add one or more nicotine shots without needing a separate mixing bottle.

A typical 60ml shortfill contains 50ml of 0mg e-liquid, leaving room for one 10ml nic shot. A 120ml bottle commonly contains 100ml of liquid and has space for two shots. You will also see 30ml, 75ml and 200ml options, although the 50ml and 100ml fill sizes are the most familiar choices.

The format is shaped by UK rules on nicotine-containing e-liquid, which is generally sold in bottles of no more than 10ml. Shortfills let adult vapers buy a larger nicotine-free bottle, then add separately sold 10ml shots to reach their preferred strength.

For vapers who already know the flavours they enjoy, this can be a practical, cost-conscious alternative to repeatedly buying smaller bottles. It also means there is a huge choice of shortfill flavours, from straightforward fruit and menthol blends to dessert, sweets, tobacco and drink-inspired profiles.

Why choose a shortfill?

The main reason is value. Larger bottles normally work out cheaper per ml than 10ml e-liquids, particularly if you vape regularly. They are also convenient: one properly mixed 60ml bottle can last much longer than a 10ml bottle, depending on your device and daily use.

Shortfills give you control over nicotine strength too. If you have stepped down from a stronger nic salt or are moving away from smoking, you can choose whether to add nicotine at all. The same flavour can be vaped at 0mg, mixed to around 3mg, or adjusted differently with the right amount and strength of nic shot.

There are trade-offs. Shortfills are usually best suited to refillable kits rather than simple prefilled pod systems. Because they are commonly high VG, many work best in sub-ohm tanks, higher-power pod kits and devices with lower-resistance coils. They also take a little preparation, so they are not as instant as a ready-to-vape 10ml bottle.

How to choose the right bottle size

Start with how much e-liquid you get through. A 50ml shortfill is a sensible first buy if you are trying a new flavour or use a compact refillable pod kit. A 100ml shortfill makes more sense when you know you like the flavour and want to reduce the cost per bottle.

It is worth checking the bottle's stated capacity and its actual e-liquid volume. A bottle labelled 60ml does not necessarily contain 60ml of vape juice. In most cases, it contains 50ml with 10ml of headroom. The same principle applies to a 120ml bottle with 100ml inside.

Think about your device as well. Direct-to-lung kits and sub-ohm tanks can use considerably more e-liquid than a mouth-to-lung pod kit. A larger shortfill may be better value, but only if you will use it while the flavour is still at its best.

Nicotine shots explained

A nic shot is a 10ml bottle of nicotine liquid designed to be added to a shortfill. Most are sold in either 18mg or 20mg strength, and the VG/PG ratio matters if you want to keep your final mix suited to your coil.

For many high-VG shortfills, a high-VG 18mg nic shot is the straightforward option. Adding one 10ml 18mg shot to 50ml of nicotine-free liquid creates 60ml at approximately 3mg strength. Adding two 18mg shots to 100ml of shortfill produces 120ml at approximately 3mg as well.

If you use a 20mg shot instead, one shot in 50ml produces roughly 3.3mg. That small difference may not matter to every vaper, but it is useful to understand when you are choosing a strength. The final result depends on the nicotine content and volume of the shot, not just the number of bottles added.

A quick formula can help when the bottle sizes are less standard:

Nicotine strength in mg/ml × nicotine liquid volume in ml ÷ final total volume in ml = final nicotine strength.

For example, 10ml of 18mg nicotine liquid contains 180mg of nicotine. Once mixed into a 60ml bottle, 180 divided by 60 gives 3mg/ml.

Do not overfill the bottle. The spare space is usually calculated for the intended number of 10ml shots, but unusual bottle sizes can vary. If you want a strength that needs more nicotine liquid than the bottle can hold, use a clean, suitable mixing bottle rather than forcing liquid into the shortfill.

How to mix shortfill liquid safely

Mixing a shortfill takes only a few minutes, but nicotine should be handled with care. Keep bottles away from children and pets, avoid contact with skin and wash your hands if you spill any liquid. Nicotine products are for adults only.

First, remove the shortfill bottle's cap and nozzle carefully. Add your chosen nic shot or shots, replace the nozzle and cap, then shake the bottle thoroughly for at least a minute. The liquid should be mixed evenly before you fill your tank or pod.

Most modern shortfills are ready to vape after shaking. Some complex dessert, cream or tobacco flavours may taste smoother after a short steep, which simply means leaving the sealed bottle in a cool, dark place for a few days and shaking it occasionally. Fruit, ice and many sweet flavours are usually good to go straight away.

If the flavour seems muted after adding a shot, give it more time to settle before deciding it is not for you. Nicotine shots slightly dilute the flavour concentrate, although reputable shortfills are generally formulated with this in mind.

VG, PG and matching a shortfill to your kit

The VG/PG ratio affects vapour production, throat feel and how well an e-liquid wicks through your coil. VG, or vegetable glycerine, is thicker and produces denser vapour. PG, or propylene glycol, is thinner and often carries flavour with a more noticeable throat hit.

Many shortfills are 70VG/30PG. This thicker ratio is normally designed for sub-ohm devices, larger refillable pod kits and coils with generous wicking ports. Use it in a low-power mouth-to-lung pod with a small coil and you may get dry hits, poor wicking or reduced coil life.

For starter pod kits and mouth-to-lung vaping, look for a 50VG/50PG shortfill where available. These are less common than 70VG varieties but can be a better fit for higher-resistance coils. Always check the guidance supplied with your device or replacement pods before choosing a liquid.

Remember that your nic shot changes the final ratio. Adding a 50/50 shot to a 70VG shortfill lowers the overall VG level slightly. In a 60ml bottle this change is usually modest, but it can matter if your device is particularly sensitive to thicker liquids.

Shortfills versus nic salts and 10ml e-liquids

Shortfills, nic salts and standard 10ml e-liquids serve different types of vaping. None is automatically the best choice.

Nic salts are often available in higher strengths and tend to suit lower-power pod systems. They are a common option for adult smokers switching to vaping or vapers who prefer a compact kit with a stronger nicotine level. Standard 10ml e-liquids offer similar flexibility without any mixing and can be ideal for trying flavours before committing to a larger bottle.

Shortfills are generally aimed at lower nicotine strengths, particularly 0mg and around 3mg, and at vapers using more powerful refillable devices. If you need 10mg, 15mg or 20mg nicotine, a shortfill is not usually the most convenient route. In that case, nic salts or ready-mixed 10ml liquids are likely to be the better match.

Common shortfill mistakes to avoid

The most frequent mistake is choosing the wrong liquid for the coil. A 70VG shortfill may look like a bargain, but it is poor value if it does not wick properly in your pod. Match the ratio to your device first, then choose flavour and bottle size.

Another is adding a nic shot without checking the final strength. One shot is not always 3mg, particularly when the shot is 20mg or the bottle has an unusual fill volume. A quick calculation avoids surprises.

Finally, do not judge a shortfill after only a few puffs from an old coil. Sweet and high-VG liquids can leave residue over time, and a worn coil can make even a favourite flavour taste flat or burnt. A fresh coil, the correct wattage and a properly shaken bottle give the liquid a fair test.

Shortfills are at their best when the format matches your habits: choose a flavour you will happily vape for more than a day, select the right VG/PG ratio for your kit and add only the nicotine strength you actually want. That is how a larger bottle becomes a simple, better-value part of your regular vape routine.