Originally Posted by BAGoldBoy
Flying to BOS on BA and have a 5 hour layover before flying BOS to LAX on AA. Once we have transferred terminals will it be possible to check our luggage in that far in advance, if we have hold baggage - current topic of conversation with Mrs BAGoldBoy

or is there a left luggage facility in the domestic terminal ? Would rather spend 5 hours in Boston than at the airport - haven't been for a few years and want to see if the Rattlesnake Bar & Grill is still open

Try calling AA and see if they will take it that early, (i.e. 5hrs I'm assuming that you have factored in the INS delay) if they won't there is another method.
I know there is a BA desk for onward luggage, from memory it might be called the connections(?) desk, it's in terminal E landside ground floor. I'm pretty sure they do luggage transfers but you
must have it checked all the way through at LHR to LAX. You'll still need to pick it up and take it through customs + Ag & fish, but once landside head left and keep walking you should find the office, ask if you can't find it.
Then take the MBTA Harbor Express boat to Long Wharf (centre of Boston) as it's probably going to be the quickest way of getting downtown. That and some great photo possibilities from the boat

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Can't find anything about what the desk is called at BOS on BA.com, and I've just checked the Massport logan site and it's not on there, does anyone know?