Charles Schwab: "Trading occurs through a leading Electronic Market. ... Quotes are not consolidated and represent the current prices available through the Electronic Market. As a participant in the Extended Hours Trading Network, the Electronic Market may also offer access to prices available on other participating Electronic Markets, but not necessarily all venues open for EHT." Does Interactive Brokers consolidate orders and offer access to all venues during extended hours or does IB only provide non-consolidated quotes like Charles Schwab? What about Lightspeed Trading, Robert? https://www.schwab.com/public/schwab/nn/qq/about_extended_hours_trading.html
At the very least, we offer access to ARCA & NASDAQ from about 4am to 8pm ET on most software. I'm not sure what other ECNs are open and from what times. Does that answer your question?
From IB's website which has a comprehensive list. Couldn't find the info on light speeds site. https://www.interactivebrokers.com/en/index.php?f=1563
These are most of our routes on LS Trader. https://www.lightspeed.com/pricing/routing-fees/ I'm personally not sure what ECNs allow pre-market trading but if they do, I assume we do. LS Trader makes all orders live at the point of entry except certain order types. https://www.lightspeed.com/pricing/routing-fees/
I Trade on Lightspeed and provides ARCA and NSDQ from 4 am(which are the only ECN trades during these times) and EDGX adds to the list after 7am(again only these ECNs trade till this time). All ECNs except NYSE start trading after 8am. NYSE opens at 9.30.