What to pack for an autumn onsen trip in Japan
Packing for a ryokan trip is different from packing for a hotel stay, because the ryokan provides more than most travellers expect. Understanding what is already waiting in your room changes the calculation considerably and usually means you can travel with a smaller bag than you planned.
What the ryokan provides
Every ryokan provides a yukata, a towel, a small hand towel for the onsen, toiletries (shampoo, conditioner, body wash, a razor, a toothbrush), and slippers. Most also provide a thicker tanzen robe for cooler evenings. You do not need to bring any of these things.
Some ryokan also provide a hairdryer, a thermos of hot water for tea, and a small selection of local snacks. The room will have a safe for valuables. If you are unsure what a specific property provides, we can check for you before you travel.
What to actually bring
Comfortable walking shoes for the town and any outdoor walks. A pair of slip-on shoes is more practical than laces at a ryokan, where you will be removing your footwear frequently. Warm layers for the evenings. October and November in the mountains can drop to 8 or 10 degrees Celsius after dark, even if the days are mild.
Any prescription medication, clearly labelled, with a copy of the prescription in English if possible. Japan's customs rules on medication are specific, and some common medications in other countries require advance import permission. We can advise on this if needed. A small day bag for outings, a portable phone charger, and a copy of your travel insurance documents.
What most people pack that they do not need
A full-size shampoo and conditioner. The ryokan provides these, and they are usually good quality. A dressing gown. The yukata is the dressing gown. Multiple pairs of shoes. Two pairs is enough for any ryokan trip. A travel iron. The ryokan will press anything you need pressed.
Formal clothing is almost never necessary. Dinner at a ryokan is eaten in your yukata. The most dressed-up you will need to be is a neat casual outfit for any day trips into town.
The general principle is: pack less than you think you need, because the ryokan will cover more than you expect. A bag you can carry comfortably for ten minutes is the right size.