How to Add Nic Shots to 100ml Shortfills: The Complete Guide

If you’ve recently picked up a 100ml shortfill e-liquid, you might be staring at that empty space in the bottle wondering what to do next. The good news is that adding a nicotine shot – or “nic shot” – is one of the easiest things you can do as a vaper, and this guide walks you through everything you need to know from start to finish.

What Is a Shortfill and Why Is There Space in the Bottle?

A shortfill is a nicotine-free e-liquid that comes in a bottle larger than the liquid it contains. A 100ml shortfill, for example, typically comes in a 120ml bottle filled to the 100ml mark. That extra 20ml of space is there by design – it’s reserved for you to add one or two nicotine shots.

This format became popular in the UK following the Tobacco Products Directive (TPD), which limits nicotine-containing e-liquids to 10ml bottles at a maximum strength of 20mg/ml. Shortfills get around this by being completely nicotine-free, allowing manufacturers to sell them in larger volumes legally.

What You’ll Need Before You Start

Before you add a nic shot to your shortfill, make sure you have the following:

• Your 100ml shortfill e-liquid
• One or two 10ml nicotine shots (most commonly 18mg strength)
• Clean hands
• A flat surface to work on

That’s genuinely it. No syringes, no lab equipment, no mess – it’s a straightforward process designed for everyday vapers.

Understanding Nicotine Shot Strengths

The most common nic shots available in the UK are 18mg nicotine shots. When you add one 18mg nic shot to a 100ml shortfill, the maths works out like this:

1 x 18mg nic shot into 100ml shortfill = approximately 3mg nicotine strength

If you want a slightly stronger hit, adding two 18mg nic shots gives you approximately 3mg as well – wait, that doesn’t sound right. Here’s the proper breakdown:

• 1 x 18mg nic shot (10ml) added to 100ml shortfill = ~1.5mg/ml (total 110ml at 1.8mg = roughly 1.5mg once diluted – check label guidance)
• 2 x 18mg nic shots (20ml) added to 100ml shortfill = ~3mg/ml (fills the bottle to 120ml)

Most shortfill labels will tell you exactly how many shots to add and what the resulting nicotine strength will be – always follow the manufacturer’s recommendation on the packaging first.

Blueberry Sour Raspberry Nic Salt – 10mg

Blueberry Sour Raspberry Nic Salt

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Raspberry Iced Tea Nic Salt V Salt – 10mg

Raspberry Iced Tea Nic Salt V Salt

£2.99

Step-by-Step: How to Add a Nic Shot to a 100ml Shortfill

Step 1: Open Your Shortfill Bottle|

Unscrew the cap on your 100ml shortfill. Most shortfill bottles have a child-resistant cap that requires you to press down and twist simultaneously. Set the cap aside somewhere clean.

Step 2: Open Your Nicotine Shot

Nicotine shots also have child-resistant caps. Open your nic shot bottle in the same way – press down and twist. Be careful handling the liquid directly, as concentrated nicotine can be absorbed through the skin in large amounts.

Step 3: Pour the Nic Shot Into the Shortfill

Carefully tip the nicotine shot bottle and pour its entire contents (10ml) directly into the shortfill bottle. The shortfill bottle has been designed with enough headroom to accommodate this. If you’re adding two nic shots, repeat this step with the second bottle.

Step 4: Replace the Cap and Shake

Once the nic shot is in, replace the cap on your shortfill bottle securely. Now give the bottle a good, firm shake for around 30 to 60 seconds. This is important – you want the nicotine to distribute evenly throughout the liquid.

Step 5: Leave It to Steep (Optional but Recommended)

After shaking, it’s a good idea to let the bottle sit for 5 to 10 minutes before vaping. Some vapers prefer to steep their liquid for longer – anywhere from a few hours to a day – which can enhance the flavour. This is entirely optional, but worth trying if you find the taste slightly sharp immediately after mixing.

Step 6: Fill Your Tank and Vape

Once you’re happy, fill your vape tank as normal and enjoy your freshly mixed e-liquid.

Common Mistakes to Avoid

Don’t add too many nic shots. Stick to the recommended number on the shortfill label. Adding more than the bottle is designed for will overflow it and create a mess, and going above the recommended ratio can result in a nicotine strength that’s unpleasant or even unsafe to vape.

Don’t skip the shake. The nicotine won’t distribute itself properly if you just drop it in and vape straight away. A proper shake is essential.

Don’t use the wrong strength nic shot. Most 100ml shortfills are designed to be used with standard 18mg nicotine shots. Using a different strength will throw off the final nicotine level.

Don’t store your mixed liquid in direct sunlight. Once mixed, store your shortfill in a cool, dark place to preserve the flavour and nicotine potency.

PG/VG Ratios – Do Nic Shots Affect Them?

Yes, slightly. Most standard nic shots are a 50/50 PG/VG blend, which means adding them to your shortfill will subtly shift the overall PG/VG ratio of the finished liquid. For the majority of vapers using sub-ohm kits, this difference is barely noticeable. However, if you’re particularly sensitive to PG or prefer a very high VG ratio, look out for high-VG nic shots – these are widely available and will better preserve your shortfill’s original ratio.