If you have a regular and an IRA account with IB, can you quickly change from one to another during the day so you can trade both accounts? Or do you have to restart TWS in order to go from one to the other?
You can launch multiple TWS sessions. Just log into each respective account. I've had as many as 4 running at once on the same machine. It works well as long as you have enough RAM and your connection is good.
But it seems I have read something about linking accounts at IB. If this is possible, what would be the purpose of having linked accounts? And thanks for the idea of have two TWS's up at the same time. It might be the only way to have two accounts available to trade at the same time.