Yes, it is important to check individual dates, as the fares to the two cities vary. However, after 14 years of traveling to PVD (from SEA for about six years, then from MSP the last 8) about four times a year, I have found that most of the time it is less expensive to go to BOS. That has been reinforced by competition from Jet Blue in the last year or so. I usually fly to BOS, then take commuter rail into downtown Providence. The time and hassle spent on ground transportation ends up being comparable to the time and hassle of connecting flights to PVD. There used to be one conveniently timed NS PVD-MSP flight and back each day but that was dropped a few years ago.

I do this for personal travel, but assume many of the same factors would apply for business travel.