What's open and closed on Patriots' Day in Mass.

Break out your best Revolutionary War reenactment garb, it's almost Patriots' Day.

Massachusetts, Maine, Connecticut, North Dakota and Wisconsin are the only states to mark the official holiday, which commemorates battles of Lexington, Concord and Menotomy in 1775 that kick-started the Revolutionary War. Technically, Massachusetts celebrates Patriots' Day and Maine celebrates Patriot's Day, (note the little apostrophe difference).

But some refer to the day as Marathon Monday. Racers hit the streets for the Boston Marathon each year on Patriots' Day, which usually occupies the hearts and minds of those in Massachusetts and beyond.

Plus, April 15 is also Tax Day, the deadline for filing your federal income tax return, for all states except Massachusetts and Maine, which get an extension until April 17 because of the Patriots' Day. Whatever you call the third Monday in April, there are some closures to remember before you head out the door:

Federal offices: Open.

Federal courts: Open.

Post offices: Open.

State offices: Closed.

State courts: Closed.

Municipal offices: Closed.

RMV: Closed.

Public schools: Closed.

Libraries: Closed.

Banks: Open.

Stock market: Open.

Retail locations: Open.

Liquor stores: Open.

Supermarkets: Open.

Trash pickup: Check with your local government or provider. Boston residents can check for pickup delays by searching their address here.

MBTA: Operating on a special schedule due to the Marathon.