Star Alliance - Baggage on United and SAS

I am traveling to Stockholm in late July w/ separate reservations on United and SAS. I am flying Y on United and J on SAS. The flights are on the same day. Do I still have to pay for baggage on the United flight? Last year I flew AA Y and BA J on the same day but separate reservations and they didn't charge me for the bags on AA, that's why I'm wondering.

I am traveling to Stockholm in late July w/ separate reservations on United and SAS. I am flying Y on United and J on SAS. The flights are on the same day. Do I still have to pay for baggage on the United flight? Last year I flew AA Y and BA J on the same day but separate reservations and they didn't charge me for the bags on AA, that's why I'm wondering.

Your first bag is free you will have to pay for your second bag. If your flights were on the same reservations they may have waived the second bag fee.

Not so sure about that; if they agree to interline your bags (check them through) I believe the recent rule change means that SAS would be considered primary carrier (or whatever it is called) and that their rules would apply. In practice, there is probably some probability on either outcome - 50/50?