Spain
I haven't been to Spain in almost 30 yrs and it was mostly in the south, Marbella, Malaga to name a few and are very beautiful seaside towns (now big resorts) and both had topless beaches as the women I travelled with were thrilled about,also I believe as of last year that most places in Spain it is legal to be nude in public (check before...lol) go be nude and enjoy the local Paella!.....Vaya Nudista!
We are looking for beaches and hotels/resorts. Looking to go down the Costa del Sol and maybe some of the islands. Would like to go to one or two must see spots. We'll stay for a few days and then travel on to other places.
Wel spain has a very liberal tolerance for naturism. Ther are many beaches and on the most beaches you may be nude but it depends on the other visitors. Ther nudist resorts in spain. You can look on my website to find them https://members.quiknet.nl/naturist . Look at Spanje and then beaches or appartementen . You als can loo at https://www.simonnoot.nl
Ther ar also b&b.
Barcelona has a nice nudebeach and is a wonderfull city.
NAturistNl
If you aim for the Costa del Sol and/or nearby areas as you stated, then Costa Natura and Vera Playa are the main resorts there, should you prefer 24/7 nudity. Vera Playa is near Almera and Costa Natura is next to Estepona (as an excursion bonus it is just a short drive from Gibraltar as well as fast boats to Morocco from Gibraltar, Algeciras and Tarifa).
In case you want to be more in the "core" Costa del Sol, there are only a few beaches, no resorts. West of Malaga best beaches are Benalnatura in Benalmdena part of Nuova Torrequebrada and Cabopino (I guess it is part of Mijas-Costa but not sure) between Funegirola and Marbella. First is a small club-run small cove with a nice small bar where nudity is virtually mandatory. Cabopino is a few km long stretch of beach west of a marina and a moat, strictly clothing optional but not bad as such.
East of Malaga there some nice nude beach spots, too, but know them too little to give any thorough evaluation.
Enjoy your trip!