weiss es niemand???

initial credit? starting credit??

... weitere Kommentare abwarten...

oder: starting balance

Es gibt kein aleinstehend wort.

initial balance seems to be the most commonly used term in English on the internet, and it sounds the best to my ears as a native speaker, although starting balance also sounds ok.

This account has an opening balance of . . .

I agree with Linda's assessment. In a certain context, such as an answer to the question, "What is the revenue history of this account?" could be answered with, "Sir, the initial account balance was...", or "Madam, the starting account balance was...".

Another context might answer the question, "With what amount was this account opened?". An answer could be, "The opening account balance, madam, was..."

So there are three possibilities:
1. opening account balance
2. initial account balance
3. starting account balance

#6: you've resurrected this thread and then ignored the stated context. It's to do with credit on a mobile phone not a bank account.

Thanks for the feedback Spike BE, but the comments in #6 apply equally to a starting balance for a cell phone or a bank account. Both can involve a starting balance. I happen to work in the telecommunications area for one of the largest cell phone companies here in Germany, and I am fluent in German. The comments presented in #6 are perfectly correct, absolutely valid, and I have ignored nothing.