The new duty is a flat rate of £2.20 for every 10ml of vaping liquid. That rate applies whether the liquid contains nicotine or not, and whatever device or container it is sold in. A prefilled pod, a disposable vape, a cartridge or a simple bottle of e-liquid are all charged according to the volume of liquid they contain, not according to the type of device itself.

There is one meaningful exclusion. Products that are licensed medicines intended to be vaporised are not covered by the duty. Everything else sold as a vaping liquid, regardless of strength or flavour, falls within scope from today.

Unlike the new retailer registers now appearing elsewhere in the UK and Scotland for products such as nicotine pouches, Guernsey and Alderney have not set up a separate registration scheme for this duty. Instead, it is collected in the same way as existing tobacco and alcohol duty: through a Customs Declaration made at the point goods enter the Bailiwick. That covers a freight shipment brought in by a shop, a parcel ordered by post from the UK or overseas, and an individual bringing liquid in for themselves.

Businesses and importers carry the responsibility for making sure that declaration happens and the duty is paid, not just the shopper at the till. Ahead of commencement, Guernsey's Treasury lead, Deputy Charles Parkinson, said the States government had been "working closely with businesses and importers so they understand the new requirements before the duty is expected to come into force on 9 November 2026."

• Existing stock is not taxed retrospectively. Liquid already imported into the Bailiwick before 9 November 2026 is not caught by the new duty, so some shops may keep selling existing stock at pre duty prices for a while rather than every price changing on the same day.
• Medicinal products are excluded. Any product that is a licensed medicine intended to be vaporised sits outside the duty entirely.
• A personal travel allowance applies. Anyone arriving in Guernsey or Alderney can bring in up to 50ml of vaping liquid for their own use without paying the duty, the same approach already used for the UK's own personal travel allowance and for Jersey's equivalent rule. You can read more in our guide to the UK's 50ml travel allowance, though note that each jurisdiction's own allowance is set under its own separate law.

Guernsey and Alderney are the third part of the British Isles to introduce a vaping liquid duty within the space of a year, following Jersey and then the UK mainland. Each of the three sets its own rate and its own collection method, because each is its own separate tax authority. We first explained the Guernsey and Alderney measure when it was announced, in our original article on the Guernsey and Alderney duty; this piece picks up from today's commencement with the detail that only becomes available once a measure is actually in force.