How to Pack Shoes in a Suitcase

• Wear the heaviest, bulkiest pair onto the plane
• Pack the second pair sole-to-sole, in the base of the bag
• Fill the insides — socks, underwear, chargers, a rolled t-shirt
• Bag them, or at least put a shower cap over the soles
• Three pairs is the decision that turns a carry-on trip into a checked one

The arithmetic nobody does

Shoes are the worst-behaved objects in a suitcase. They are rigid, so they will not compress. They are hollow, so they waste their own volume. They are an awkward shape, so they will not tessellate. And they are dirty, so they need separating from everything else.

Two packed pairs of trainers is a fifth of a 40 L carry-on gone before any clothing. Three pairs plus a week of clothes does not fit in a carry-on, and the realization usually arrives at eleven at night the day before a flight. What a carry-on actually holds.

Rule one: wear the worst offender

The heaviest, bulkiest pair goes on your feet. This is free capacity — clothing worn is clothing that does not count against any published limit anywhere — and it is the single largest saving available in this whole category.

On a carrier publishing a cabin weight cap, boots on your feet rather than in the bag can be two pounds of allowance, which is a day of clothing. Which carriers publish one.

Rule two: shoes go in the base, over the wheels

In a wheeled case, the wheel housings intrude into the bottom corners and create recesses that flat-packed clothing cannot use. A shoe is exactly the right shape to sit over one.

• Soles down, toward the wheels. The heaviest, dirtiest part of the bag ends up furthest from your clothes and lowest when the case stands upright.
• Sole to sole, toe to heel. Two shoes facing opposite directions nest far better than two pointing the same way — the widest part of one sits beside the narrowest part of the other.
• Along the hinge edge in a clamshell case, so the depth of the shoes is over the deepest part of the bag.

In a backpack the equivalent is different, and it matters: shoes are dense, so by the rule that governs where weight goes in a pack they belong in the middle against your back, not in the base. A backpack is not a suitcase stood on end.

Rule three: never pack an empty shoe

A shoe is a container you are already carrying. Leaving it empty wastes several liters per trip, and filling it also helps the shoe keep its shape.

Rule four: separate the soles, cheaply

Shoes are the dirtiest thing in the bag and they sit against your clothes. This does not need a product.

• A supermarket bag around each shoe. Free, weighs nothing, and works exactly as well as anything sold for the purpose.
• A hotel shower cap over the sole — the classic answer, and it leaves the upper breathing.
• A dedicated shoe bag if you want one, understanding it is a few ounces of walls for a job a plastic bag does at zero weight. The overhead budget for organizers.

The one thing worth spending on is a bag for wet or muddy footwear, because that is a different problem — a sealed bag stops damp transferring into a case where it will grow mold in a closed bag over a week.

The two-pair rule, and how to make it work

For carry-on travel, two pairs total: one worn, one packed. Making that survivable is a footwear-choice problem rather than a packing one.

1. Pick one pair that covers two situations. A dark leather sneaker or a plain low boot handles a dinner and a day of walking. Two single-purpose pairs is what pushes you to three.
2. Wear the bulky one, pack the flat one. Boots on your feet, dress shoes in the bag — never the reverse.
3. Sandals or flip-flops do not count. At roughly 1 L they are a rounding error and they solve the hotel-bathroom and beach problems for almost nothing.
4. If you genuinely need three pairs, you are checking a bag, and that is fine — decide it at home rather than at a gate. When checking is worth it.