"I have no money on my cell phone account" or "my cellphone is out of money" or how?

Solution 1:

I would say:

I'm almost out of phone credit.

If the context was clear (i.e. you were holding your phone or speaking on the phone) you could even just say:

I'm almost out of credit.

Solution 2:

Many people say "minutes" to refer to cell phone credit (because cell phone plans often measure your available balance in minutes of talking time). In my experience it's common to say "I'm almost out of minutes" or "I have only 10 minutes left on my plan" or something similar. (This is from an American perspective, if it matters)

Solution 3:

My credit balance is near finished

Or you could say what we usually do in India

I have expended my cellphone balance

Solution 4:

My mobile is almost out of credit

I'm not sure on the context for this question, but the above states the case. I regard the implications (that I will not be able make calls when out of credit) as implicit.