Portland area has some of the best options to soak up all the alcohol from the night before or some additional hair of the dog that bit you. Hover over the name if you’re not on mobile to see breakfast/brunch specific hours.

Holy Donut - Parkside194 Park Avenue
Portland, ME 04101
Critically acclaimed Maine potato donuts. They're all amazing but the Dark Chocolate Sea Salt and Bacon Cheddar are outrageous. Better spot to hit if you're just passing through.
Holy Donut - Old Port7 Exchange Street
Portland, ME 04101
" - Easier option if you're hitting up the Old Port and staying awhile. Mob scene with lines out the door during peak weekend hours and when cruise ships come in.
Standard Baking Company75 Commercial Street
Portland, ME 04101
Pastries to die for and the best croissants and pain au chocolat you'll find anywhere close by. Gets pretty damn busy with tourists when ferrys/cruise ships come in
Bayside American Cafe98 Portland Street
Portland, ME 04101
Formerly Bintliff's - Portland institution and busy at peak hours all year long for a reason. They have some of my favorite breakfast options in town.
Hot Suppa703 Congress Street Portland, ME 04102Southern style comfort foods. Fried chicken and waffles, fried green tomato BLT, etc. etc. Like lots of other places in this list it's hard to get a party of 4+ in between 9-12 on the weekends without a wait.
Caiola's58 Pine Street
Portland, ME 04102
Recently purchased by the owners of Piccolo and Blue Rooster but the focus on Italian comfort foods hasn't changed. I'd expect to see some menu tweaks in the future though.
The Front Room73 Congress Street
Portland, ME 04101
Awesome spot at the top of Munjoy hill with a great atmosphere and staff.
Piccolo111 Middle Street
Portland, ME 04101
Tiny spot that puts together an amazing Italian Sunday brunch. Reservations are recommended unless you're going early.
Schulte & Herr349 Cumberland Ave
Portland, ME 04101
Best German spot and killer breakfast/brunch options. Latkes, schnitzel, brats, spatzle, Sunday roast... sooo tasty. BYOB as well
Becky's Diner390 Commercial Street
Portland, ME 04101
Very busy diner right on the working waterfront. They serve breakfast all day/night.
Marcy's Diner47 Oak Street
Portland, ME 04101
CASH ONLY - Owner/Cook has gotten some media attention for yelling at loud parties. =) Rotating selection of amazing griddled muffins, omelets and the traditional diner fare.
Dutch's28 Preble Street
Portland, ME 04101
Their non-standard breakfast sandwiches are on point [best biscuits in town IMHO.] Saturday they mix it up with fresh batches of filled donuts with flavors like toasted almond cream with wild Maine blueberries or milk chocolate mousse with white chocolate rice crispies. Amazing.
Palace Diner18 Franklin Street
Biddeford, ME 04005
More than worth the trip to Biddeford. Some of the best fried chicken I've ever had in my life and the challah french toast is out of this world.