New measures in place from 27th June 2021 until 13th July 2021
Read here the official decree: https://www.borm.es/…/anuncio/ano/2021/numero/4475/pdf…
“2.1. In private vehicles with up to 9 seats (including the driver), in which *ALL passengers live together*, all seats can be used.
2.2 In private vehicles with up to 9 seats (including the driver), in which NOT ALL of the passengers live together, up to two seats per row may be occupied.
Although, in public transport with up to 9 seats, if all passengers are from the same address, they may sit up to three seats in each row, although the seat next to the driver must remain empty.
2.3 In vehicles in which there is only row of seats, (e.g vans, lorries etc), and if both passengers do not live in the same household, a maximum of two people may travel together (maintaining the maximum distance between them as possible).
2.4 Whenever at least ONE passenger within the vehicle is from another household, face masks must be worn by all passengers.
2.5 The vehicle must be regularly aired whether that be by opening windows or by using air con system.
These restrictions will not apply to public health transport collective, in which the greatest separation between passengers must be sought, leaving a space between seats free when the occupancy level allows it.”
SO, in conclusion, now 4 people that do not live together are allowed in a 5 seater car for example
And masks still obligatory when travelling with others which are not from your same household.