Not unless you have 150 amp service you can't. Most times the POCO only sizes the wire to the service provided, they usually aren't known to oversize the wire; ie: 200 amp rated wire for a 100 amp service. You'd have to call your poco and see what size service you have, I know in my area they offered to send out a tech to check the meter/wiring to verify what was installed for my main panel was correct (that it wasn't rated for larger than the meter/wire/service could handle). In my case the existing main panel was 150 amp, and the wire is sized for 150 amp service (no upgrading the extra 50 amps to 200 with out upgrading the wire).Can a 100 amp main panel be changed to a 150 amp main panel simply by changing out the box? I don't want to upgrade to a 200 amp for cost reasons. Someone told me there is a way to upgrade to 150 amp service if the wires are rated correctly. Possible?