These SMSCs has been verified to work for sending international messages (see comment above):
+46 740930000 (Sweden/Telia)
+32 495955205 (Belgium/Mobistar)
+31 653141414 (Netherlands/KPN)
+41 794998990 (Switzerland/Swisscom)
The SMSCs below are reported to support the UCP protocol, but may only work for national or their own subscribers:
+47 90002198 (Norway/Telenor)
+45 43625250 (Denmark/TeleDanmark)
+358 209801 (Finland/Sonera)
+49 1722278020 (Germany/D2)
+354 9541010 (Island/Landssími Íslands)
+351 962113000 (Portugal/TNM)
Using international SMSCs
I get a lot of questions from users using a GSM operator without an UCP SMSC. To use other international SMSCs you have to use your telcos normal international prefix for the call, not the + prefix you usually use on international calls on your phone. E.g. to use Telias SMSC at +46740930000 (Sweden), use 0046740930000 if 00 is your operators international prefix.
The same goes for the reciever of the message, but here you have to use the SMSC operator's international prefix. For the SMSC above that is 00, so to send a message to an UK phone use 0044 and the phone number. The number you want as sender you pass the normal way, the message will be recieved with no changes on this number.
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