If you're in Canada and fancy a cheap lunch this autumn, put November 3 in your diary. MR.SUB, the homegrown sandwich chain that's been slinging subs since 1968, is marking National Sandwich Day with a one-day price drop: Small Classic Deli Subs for just $6.68 — the number a nod to the year the brand was founded.

The deal covers the chain's Classic Deli lineup, so you can pick from the Assorted, Turkey, Ham, Italian Salami or Pizza Sub, then pile on whatever toppings you like. Regulars will tell you not to leave without the signature '68 Sub Sauce, the house recipe that's been part of the brand's identity for decades.

One catch worth knowing: the offer is online-only. You'll need to order through MR.SUB.ca or the MR.SUB app on the day, so it's worth downloading the app in advance rather than fumbling with it at noon on November 3.

There's also a bigger prize up for grabs through the rest of the month. Every eligible MR.SUB purchase made in November — in-store or online — earns Rewards Members an entry to win free Large Subs for a year. The catch here is that the contest is exclusive to MR.SUB Rewards Members, so sign up before you order. Scan your card in-store or log into your account online, and note that each eligible visit counts as a separate entry, meaning frequent lunch runs genuinely improve your odds. Full terms are on the chain's contest page.

For travellers, this is a low-stakes excuse to try a genuine Canadian fast-food institution. MR.SUB predates most of the big American sub franchises in Canada and has a loyal following, particularly in Ontario and the Atlantic provinces. If you're road-tripping or city-hopping in Canada in early November, a $6.68 sub is about as painless a lunch as you'll find — and National Sandwich Day makes a fun, if manufactured, reason to join the queue.