Family for all.

You have several places in Porto if you desire put our luggage in a locker.

Tube Station: Estação da Trindade; (on the way to Porto Airport, opening hours: 6 a.m. to 1 a.m., maximum usage time 7 days).

Train Station of Estação de Campanhã; (on the way to Porto Airport, maximum usage time 24 hours).

Train Station of Estação de São Bento; (right in the center of Porto downtown, maximum usage time 24 hours).

Porto Welcome Center; (is an Interactive Tourist Tourism Store of Porto and North, it is in front of the Train Station of Estação de São Bento). You can leave the luggage at the hours that they are open.  

If you prefer a more personalized service you can try some companies that provide this kind of services and others inside the city like for example dressing room and wash basin with hot water.

All options above are paid.