I'm looking to upgrade my current service panel from 125Amp to 200. I had a journeyman electrician tell me that this could be done very easily. I've tried to do some research myself but am still a little confused. There is a thick black cable coming into the panel that says 1AWG on it. The meter on the outside states FORM 25 CL200 240V 3W 60Hz TA=30 Kh 7.2. Based on information that I've googled I'm still trying to determine if the 1AWG is capable of handling a 200AMP service. Any info to help me out is greatly appreciated!

Okay, to begin with your journeyman is correct and foolish at the same time.
Simplisticly, yes it is a straight forward project, however, that said, it is not necessarily a DIY project.


To begin with, you need to start this conversation with your power company. They own the connection points between the transformer and your meter base.

They will determine who and how the connections from the transformer to the home will be made. In my area, Virginia Beach, VA, the PoCo owns everything between the meter base and the transformer. They will set the cable size and make the connections, if a 200 amp service is available.

The city will require a permit and will allow a homeowner to pull the permit and do the work providing that homeowner can prove they are capable of doing the work.

It is not just a simple panelboard change. You would be wise to contact several licensed electricians for bids. Working on 240 V 200 amp can prove to be deadly if you do not know exactly what needs to be done.

To answer you question... for a 200 amp service you would need either a 2/0 copper or 4/0 alum cable.
The 125 amp panel SHOULD have either a #2 copper or 1/0 alum cable. Is you panel feed copper?