What should I pack for a hostel stay in Portugal?

A padlock is essential — most hostels have lockers but don't supply locks. Get a combination lock so you don't worry about losing keys. TSA-approved combination models are lightweight and double for airport luggage security. This is probably the single most important hostel item.

Flip flops for the hostel shower and a quick-dry travel towel. Most Portuguese hostels provide towels but some charge €1–2/day rental. A compact microfibre towel takes almost no luggage space and dries in an hour. Also pack a sleep mask and earplugs — lifesavers in shared dorms.

For Portugal specifically: pack light layers rather than heavy clothes. Even in summer, Lisbon evenings can be cool and air-conditioned restaurants feel cold. A light hooded jacket covers beach days, cool evenings, and casual dining all at once. Don't overpack.

In summer (June–September) bring high-factor sunscreen. The Portuguese sun is significantly stronger than Northern European sun, and sunburn on day one will ruin your trip. Sunscreen is also noticeably more expensive to buy in Portuguese pharmacies than to bring from home.