# The pre-flight shopping checklist

Airside time is short and badly suited to arithmetic. Everything that can be decided at home should be decided at home, so the twenty minutes you have in the shop are spent choosing between bottles rather than working out whether to buy one at all. This is the whole list.

## 1. Know the price at home

Look up the exact bottle where you would normally buy it, including whatever promotion is running this week. That figure, not the shelf's promise, is the number the airport has to beat. Write it down; you will not remember it at the gate.

## 2. Convert everything to a common measure

Airport shelves favour the litre, home shelves favour 70 or 75 centilitres, and fragrance comes in half a dozen sizes. Price per litre for bottles, price per millilitre for fragrance. Do it once, at home, for the two or three things you are actually considering.

## 3. Check the allowance for where you land

The limit belongs to the arrival country, it is written in litres, and it applies per eligible traveller. Look it up on that country's own customs website. Going over is allowed if you declare it and pay; being found with an undeclared excess is not.

## 4. Decide which airports are in play

If you pass through more than one airport, you have more than one shelf. The same bottle at the same retailer routinely differs between them, and the connection you were treating as dead time may be the better shop. [Set your airports](/savings) and let the comparison run across exactly those.

## 5. Sort the loyalty scheme before you fly

Where the retailer runs one, the member price is the one on the receipt. Signing up at the counter works but costs you minutes you will want for something else. Do it the night before.

## 6. Plan the carry

A litre of spirits is heavy, glass is fragile, and liquids bought airside travel in a sealed bag that must stay sealed through any onward security check. If you have a connection outside the customs area you are landing in, check that the sealed bag will be accepted, or buy on the last leg instead. Where the arrival airport has a shop, buying on the way in solves the problem entirely.

## At the shelf

With those six settled, the shop becomes simple. Read the local currency price, ask whether a member price applies, check the size against what you priced, and look at the date on any comparison you are carrying. If the airport wins, buy it. If it does not, you have lost nothing but the walk, and you already know where the same bottle costs less.