For your 2026 ferry journey into the UK from outside the country (including the EU), you must adhere to strict "High-Fidelity" customs allowances to avoid duty charges. Each person aged 17 or over can bring back 4 litres of spirits (over 22% ABV) OR 9 litres of sparkling/fortified wine (under 22% ABV). You can mix these two, but only up to 100% of the total allowance. In addition to that, you are permitted a generous high-fidelity allowance of 18 litres of still wine and 42 litres of beer. It is a high-fidelity requirement to remember that these allowances are for personal use only; if customs officers suspect you intend to sell the alcohol, they can seize the goods regardless of the volume. If you exceed these limits, you must declare them via the "Online Service for Passengers" before arrival to pay the necessary UK taxes. Note that you cannot "pool" your allowances with other travelers to bring in larger individual items.