calling to the US from Cell phone+

Hi, I know last time I was in Mexico, I had to dial something like 001 + area code + phone number to call to the us from cell phone. Is that right???
Thanks

You are correct. Be sure to have international roaming set up on your cell phone. I would suggest that you go to your service providers website and check coverage maps/international calling etc..
Calling to U.S. or Canada:
001 + area code + 7-digit number