Madrid or Málaga, the same verdict
What a Spanish connection looks like from outside
Paramount+ reads the public address a request arrives from, and every consumer connection in Spain supplies a Spanish one. Madrid, Barcelona, Valencia, Seville, Zaragoza, Málaga, Murcia, Palma, Las Palmas, Bilbao, Alicante, Córdoba, Valladolid and Vigo all answer identically. The province is not the variable.
The variable is your operator — and Spain has one of the densest fibre networks in Europe, so the operator serving your building may well be one you have never heard of outside your own city.
The CG-NAT-free two
Movistar and O2
The only major Spanish operators that leave residential customers on an address of their own. If you are on either, your line is already more individual than most of the country’s — which does not change the Spanish verdict, but does change what a US-address test is correcting.
The CG-NAT majority
MasOrange and its brands, Orange, Jazztel, Digi, Finetwork
A Spanish address, shared with a substantial number of other subscribers. MasOrange will lift it free if you ask; Digi sells a public IPv4 for around €1 a month; Finetwork does not offer a way out that we could find documented.
Mobile and tethering
Movistar, Orange, Vodafone, Yoigo, Digi and the resellers
A Spanish address, effectively certain to be shared, and with Spanish IPv6 adoption low the vast majority of that traffic is IPv4. Convenient for a quick check, poor ground for a controlled test.
Office, campus, hotel, Renfe
Corporate networks, universities, hotel Wi-Fi, on-board Wi-Fi
A Spanish address, and many of these block tunnelling protocols as a matter of policy. A failure on one of these tells you about that network. It tells you nothing about your account or about Paramount+.
Two things follow from this that are specific to Spain. First, if you are on MasOrange, one free request improves your own line before you buy anything at all. Second, because IPv6 is scarce here, a Spanish test is usually a single-protocol test — simpler to read than the equivalent in Paris or Munich, and correspondingly easier to trust.