The code is silent on the specific length, but someone did point out a relevant section. This issue is how far can a service conductor come into a building before it must terminate in the building disconnect. Here in Washington, it is 15 feet. Some places it 10' or 5'. You'll have to ask your inspector or read any local codes to see how far a service conductor can come into a building before being terminated.
And as someone else mentioned, the location of the meter is not relevant. You can run 50 feet of conduit on the outside wall past the meter before entering the structure. But once you poke a hole and come inside the house, there is a limit on service conductor length.
