Simple Tides / Guides / Portland Tides

Portland, Maine Tide Chart

Portland answers to some of the biggest tides in New England — nine to ten feet of semidiurnal swing that empties harbors, exposes vast flats, and rips current through Casco Bay’s island-dotted passages.

The pattern

Two highs and two lows daily with a nine-to-ten-foot range — more on the spring tides near full and new moons. That much water moving means serious current in the bay’s narrows and a harbor that looks completely different at high versus low water. Ramps and moorings go tide-dependent.

Stripers and mackerel

From late spring through fall, striped bass prowl Casco Bay’s ledges and river mouths, with the tide change the prime trigger — fish the moving water around structure. Mackerel blitzes light up the bay in summer. The Presumpscot and Fore rivers concentrate fish on the ebb.

Boating and the islands

Time island crossings with the current in your favor, and never trust a dinghy left floating at high tide — a ten-foot drop leaves it high and dry or dangling. The mail-boat run and ferries to the islands run tide-aware for a reason. For the region, see our New England tide guide.