Not exactly, TP own PTS and City Plumbing Supplies, somewhere along the lines there are various systems tied in to each other but it's not just a case of City Plumbing is the same as PTS. I can go into City Plumbing and put stuff on my TP account, I can't go into City Plumbing and put stuff on my PTS account, and I can't go into TP and put stuff on my City Plumbing account.And city plumbing are the same as PTS
Some of this might depend on the aptitude of the member of staff who is dealing with you at the time as well. It's not as smooth as you would expect once you get into it.