ZitatAlles anzeigenOriginal geschrieben von geos
If you frequently need to make calls, particularly longer ones, to Finnish landlines, get a German prepaid or postpaid tariff with unlimited calling to German landline numbers for a flat monthly fee. You can then use callthrough to reach your destination. According to http://www.teltarif.de/db/res-…nwahlnummer&ziel=Finnland callcheap.de offers free callthrough to Finnish landlines.
I would be cautious to better avoid the O2 and E-Plus Networks because they tend to block callthrough numbers. Telekom to the best of my knowledge does not make any restrictions in that respect.
An overview of prepaid-based offers which include unlimited calls for a flat monthly fee can be found here:
http://www.prepaid-wiki.de/index.php5/Übersicht_Flatrates
It's probably outdated though and it lacks for example Congstar (which I think could be a good choice for that purpose).
If you are not into callthrough that much, you might want to check out http://www.teltarif.de/mobilfunk/tarifrechner.html to find suggestions for suitable tariffs for directly calling abroad.
Thanks a lot for the information and the useful links geos.
I've already had NoNoh VoIP (a Betamax clone) and now I'll used from my smartphone through their mobile app. Calls to Finnish landlines are free and to mobiles is 6c/min. They have 7 callthrough German numbers and none of them is blocked from E-plus/Ring.
Even if Ring blocks the NoNoh access numbers they offer an alternative option for calling, through callback (they call it Phone-to-Phone) which is equally cheap. (http://www.nonoh.net/en/phone-to-phone.html)
Again, thank you all for the invaluable help and information.