Is your friend with MTS or one of the other providers? Where is he located?
If he is with MTS and gets a call from Manitoba then yes there will be a LD charge unless he has a long distance plan. I think the cost to upgrade to unlimited LD is around $17 a month
The exception for this is he is in Cottage Country around Lake of the Woods up to Clearwater Bay in Ontario where MTS has coverage and then it would be considered "Manitoba" by the billing system. He would have to check a MTS coverage map to see if he is in the area if he does not know off hand