The leaves don’t care about your holiday calendar. They change on their own schedule, rolling south and coastward throughout September and October like a slow-motion fire across New England and Canada. Your job is simply to meet them halfway. Here’s how to time the colour, pick an itinerary that delivers it, and know where to linger when the foliage show peaks.

When to go (and why timing is everything)

Colour moves from north and high ground → south and coast. In practice that means:

• Northern New England first, coastal Maine last. New Hampshire’s official tracker shows typical peaks sliding from the White Mountains down toward the seacoast across late September into October; weekly reports refine that once the season starts.
• Maine’s coast can peak mid to late October. The state’s foliage service publishes weekly maps; their 2024 season wrapped with coastal areas peaking mid-October, which is a good rule of thumb for Bar Harbor and Portland on leaf-chasing cruises.
• Québec City and Atlantic Canada are prime in early to mid-October. Destination Canada and Québec City’s tourism board both flag late September into early October for the brightest displays in eastern Canada, which lines up neatly with St Lawrence itineraries.
• Acadia National Park (Bar Harbor) usually peaks mid-October. That’s straight from the National Park Service, which also points visitors to Maine’s weekly foliage site for in-season updates. 

UK planning tip: if you’re choosing between sailings, a departure in the first half of October tends to catch both New England and the Canadian Maritimes in strong colour on one trip.

Itineraries that deliver colour

You’ll see two classic patterns:

• Round-trip 7-day loops from Boston or New York calling at Bar Harbor (Acadia), Portland, Saint John (Bay of Fundy) and Halifax. These stack the odds for seeing the best of the Maine maples plus Nova Scotia’s reds and golds. Examples run all season with major lines.
• One-way 10–12 day sailings between Boston/New York and Québec City, adding Sydney (Cape Breton), Charlottetown (PEI) and an overnight or late stay in Québec City. They push further into the St Lawrence for big-screen river scenery and longer days ashore. 

If you want the deepest colour in one go, look for the one-way Boston ↔ Québec window around early to mid-October. (Multiple lines schedule those then for a reason.) 

Ports worth lingering in when the leaves pop

Bar Harbor (Acadia National Park)
Cadillac Mountain and the park’s carriage roads put you in the thick of hardwood colour. Mid-October is the typical bullseye; even a half-day loop to Jordan Pond delivers the palette. 

Halifax, Nova Scotia
Do the 4-km harbourfront boardwalk at your own pace (museums, markets, patios), then if time allows, add a shore trip to Lunenburg, a brilliantly painted UNESCO town on the South Shore. It’s pure autumn postcard country. 

Cape Breton (Sydney)
If your itinerary includes it, the Cabot Trail in Cape Breton Highlands National Park is a top-five foliage drive in North America, with many look-offs timed perfectly for October.

Saint John, New Brunswick
Time your stop for the Reversing Rapids on the Bay of Fundy — the tide literally turns the river. It’s a neat “only here” phenomenon that pairs well with a harbour walk and a café. 

Québec City
Old Québec is UNESCO-listed and built for autumn wandering: citadel views, parkland on the Plains of Abraham, and maples lighting the bluffs along the St Lawrence. Peak colour commonly hits late September into early October. 

Picking the right sailing, briefly

• Aim for the first half of October if you want one itinerary that catches both sides of the border in colour.
• Choose itineraries with longer calls in Bar Harbor, Halifax or Québec City; colour is best on foot and from lookouts, not just the sail-in. (Many one-ways build in overnights or late departures in Québec.)
• Don’t skip the Bay of Fundy. It’s not about leaves alone, the tidal show is unique to this route. 

Practical bits for a UK audience

• Paperwork: most UK travellers use the US ESTA under the Visa Waiver Program (needed if your cruise begins/ends in the US). For Canada, eTA is for air travel; arriving by cruise ship you don’t need an eTA, though you still need your valid passport and to meet entry rules. Always check the official sites before you book flights.
• Pack for two seasons: crisp mornings and sunny afternoons — layers, a windproof, hat/gloves for deck time, and shoes you’ll happily walk all day in.
• Balcony or big windows: gorgeous if you’ll actually use them, but the best colour is found ashore or up on the observation decks. Consider spending on longer port calls rather than a pricier cabin if budget is finite.

The upshot

Pick a sailing that moves with the colour (north and inland to start, coastward to finish) and give yourself time in Acadia, Halifax/Lunenburg, Cape Breton or Québec City. Do that, and you'll return with a camera roll filled with some seriously vibrant photos and hopefully some treasured memories, too.