Cell plan

Here's some info: http://prepaid-data-sim-card.wikia.com/wiki/Spain

I think Vodafone might be the best one. But since you'll be doing a very small amount of phone calls -- I might recommend instead of doing a SIM card, just getting a portable Wifi that you can put in your pocket/bag/etc. You can use your own phone (with the data turned off of course) and since you'll be only doing a very small amount of calls, you can just use Skype, etc. to place calls. http://www.wifivox.com/index.php/product

Thanks for the wifi suggestion, but at 7 Euro by day getting a sim card will be much less expensive. I'll take a look at vodaphone plans.

I have TMobile as my cell phone carrier at home, and get free service in Europe every year. You don't mention your current provider now. It might be easier to keep your phone number and have an international plan for the time you are gone? Or not, just an idea for investigation-- or more comments from the forum. I have not had to buy a simcard.

Orange is one of the bigger carriers and I find their coverage and service to be extremely reliable. We live on the border of Spain and Portugal and have no problems with the service as we switch between countries, including in fairly rural areas. We also recently (April) drove from Spain up to Lithuania, traveling through France, Germany, Czech Republic and Poland with no breaks in phone or data coverage, and 4g most of the way. And by the way, no more roaming fees as you travel around Europe!
My wife is a professor and she hosts American students here every summer. Her students need to have phones to communicate with her, with their host families and for data. She has recently started to require that they all come with unlocked phones and that they purchase SIM cards in Spain because the US based international plans just aren't very reliable here.
One other point, a lot of people here tend to message and make phone calls on Whatsapp using their data plan rather than their mobile minutes.

We have ATT and i purchased the $10/day plan. we used gps and internet and that worked well for us when traveling international.

SIMYO, which is the white brand from Orange, is probably one of the best low-cost operators at present: https://www.simyo.es/ You can actually purchase the plan online if you wish, but their website is not in English. Now Simyo offers 10Gb data and unlimited national calls for 20€ (on a fast 4G line!). Another one is Tuenti -the white brand from Movistar, the Spanish carrier and one of the biggest telecoms in the world: https://www.tuenti.es/ Its page lists a very similar offer for 21€.

All telecoms have constant promotions and offers -over here we do indeed have a really competitive market.My advice would be to head to a Phonehouse shop and ask the assistant "what's the flavour of the moment"... it's difficult to keep up with all the promotions!

Yes no roaming across the EU means just that... with a Spanish SIM, you can use your phone elsewhere in the EU as if you were home. Actually, there are some restrictions, something called the "fair use clause", but for most cases, it works just as that: use your SIM as if you were home -I mean in the country you bought the SIM!

Also, as PeteK mentioned, US plans are not really worthwhile here also because they're far more expensive than most of the options you have in-situ.

Lastly, for some might sound obvious but.... make sure you bring a 4G capable phone, and UNLOCKED, of course!

Thnaks a lot for all those answers !

I will make a good look at all those options. Enric, I will have my LG G5 (that I will unlock). In trip advisor guidebook for Barcelona (2017 edition) they say that north american cell phone dont work in Spain because of the GSM band or something like that...but it's the only place i've read that so I guess I must take that info with a grain of salt. Does Symio have a good coverage in Catalonia ? Because the spanish part of my trip will only be in that region.

I'm in Canada (montreal) and roaming charge is costing an arm and a leg ! That's why I've plan to get a Sim card in Spain (and use the same in Portugal).

Elsewhere someone also suggest me to buy a SIM for data only and buy a block of time on Skype. that might be a good idea I guess.

1.) These days, all modern phones are multi-band, meaning they work on all GSM frequencies regardless where you are in the world. I would imagine yours is so, therefore it should work in Europe. Just look the specs for the magic word "multi-band"

2.) I am a customer of Movistar, so I don't know... but I would imagine it does because as mentioned Simyo is the white brand of Orange -the French multinational- which is one of the "big" ones in Europe.

3.) Tell me about that! Until last month, moving about in Europe it was a nightmare when it came to cost. I've been travelling every few months for the past 20 years... I know! But now with no roaming one can save quite a lot.

4.) As mention, I would go to the shop on arrival and ask there, the number of different options is endless so they can offer you the best offer to your exact needs. If anything, mention that you want a solution either from one of the big players or one of their white brands, but avoid third parties (those that rent their lines to the big ones). Not that they're not acceptable, but if you plan to go to certain rural areas the coverage might not necessarily be the best.

Enjoy!