Does IB charge for their Software Platform?

Tia.

 

its free as long as you do 30 USD worth of commish/mo.

edit. 10 usd/mo otherwise.

 

It is $20 if your account goes under certain balance. Check IB's web site for the details about other fees. These type of fees still apply even if you do not use IB's software platform TWS at all and just only use web-trader.