Question: Hello, we will be traveling in Germany this summer. Can we call from a US-based cell phone to a US-based cell phone while in Germany?
Answer: Yes, you can call between two US cell phones while in Germany.
If one of your cell phone numbers is (212) 555-1234, dial 00-1-212-555-1234 to call the cell phone. You can also dial the call as +1-212-555-1234 (some phones can dial a plus symbol).
Be aware that this call will be expensive. You will be incurring the cost of an international call from Germany to the US when you dial out from the first phone and an additional international roaming call from the US to Germany as the second phone receives the call. Be sure to check your international and roaming rates before making these calls.