I’m getting ready for a European trip later this year and have been researching this same issue. There are three basic choices:
1-if you have your cell service thru a large provider (Verizon, AT&T, etc), you should be able to add international calling to your plan. Depending on your provider, this can be added by the month, by the days used, or some other set of options. The advantage to this is that you keep your current cell phone number in use. You need to make sure your phone is compatible with the German network. Your provider should be able to help answer this question.
2-you can get a SIM card in Germany and install it in your phone. SIM cards can be purchased with various amounts of call, text, and data amounts, so you can buy only what you think you will need. The advantage is that this is usually the cheapest way to go. The disadvantage is that your phone gets reset with a new German number for the time the SIM is in use, so anyone who will need to communicate with you will need to be given the new number for the trip. Once you are home, put your original SIM card back in the phone and return to normal operation.
3-buy a cheap cell phone in Germany and a service card for the amount of call, text, and data you will need. Again, you will need to share this new number with everyone who needs to contact you. When you return, just turn the phone off, pull the battery, and store it for use on some future trip. Or sell it. Advantage: can be a cheap option. Disadvantage: the whole different number drill.
I, personally, am going with option 1, since there are too many people who might need to contact me. I want to have my familiar number and all the services connected to it fully functional while I am traveling. But that’s neurotic, control-freak me. Your mileage may vary.
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