It will be both stupid and busy. And stupidly busy.
You will get the feeling any time a few days earlier without it being packed with celebrators.
It's a disaster on haloween - very rowdy - not family friendly.
I think the above advice is good. If you can go before Halloween, your family will have a more enjoyable day (but still expect crowds!). If you decide to go on Halloween, I'd suggest leaving before dark; the city works hard to minimize rowdy behavior, but it is more of an adult event than one for kids/teens.
Thank you everyone for your replies. It’s made our mind up we’ll go the day before or even on the Monday. We’re hoping to get the train there and back. Is this from North station?
Read somewhere, you can get a boat there and the train back, is that correct?
Also I believe the celebrations start the first day of October, is that also correct.
Yes, you can travel to Salem via the Salem Ferry and the MBTA's commuter rail (Newburyport/Rockport line). You can use either one round-trip (small discount for round-trip on the ferry) or one of them to Salem and the other back to Boston. Your choice. Here are links to more information:
And, yes, the official celebration is called Haunted Happenings and it takes place during the entire month of October. More information here: