I've only ever activated conditional CF to my US number (while in Canada) and haven't incurred any roaming fees while away. My father forgot to activate CCF before crossing the border but did so about an hour into the US. I don't think he was charged roaming either (he might have activated unconditional CF).
Originally Posted by WorldIRC
If one activates CCF while in Cadana and then pulls the SIM before leaving, how could you ever be charged for roaming as your SIM would never be on a foreign network. Actually on one trip to Jamaica last year, I enabled CCF in Canada but left my SIM in until I arrived in Jamaica. I even received the text warning about roaming. I pulled the SIM shortly after and wasn't charged any roaming for the calls I received. The same applies while I was in Europe. I disabled data and data roaming in TO but left my SIM in until I obtained a local SIM so I was on the foreign networks. CCF was enabled in Canada and no roaming fees for that trip either.
64GB iPhone 6, unlocked 32GB iPhone 5 (AWS), unlocked 16GB iPhone 4
Unlimited airtime, Unlimited CAN/US long distance, Unlimited SMS to CAN/US wireless numbers
2500 Call Forwarding minutes to CAN/US numbers
Google Voice for visual voice mail with message transcription, conditional greetings, unlimited messages (vs 35 message cap), remote retrieval from any PC or phone, no auto-purge after 10 days and most importantly no $7-$8 charge.