FamilyMart Upgrades Yakiimo, Japan’s Warming Winter Treat

Oden has its broth, its daikon and its devoted followers. But Japan’s colder months have another familiar comfort: yakiimo (焼きいも), roasted sweet potatoes eaten warm, their skins pulled back to reveal the soft flesh beneath.

This season, FamilyMart is giving that winter staple an update. Its revamped Yakiimo (焼きいも), priced at ¥298 including tax, arrives on Tuesday, October 20, 2026, at about 5,600 stores across Japan, excluding Okinawa.

A Little Foil, Two Hours of Patience

Each potato is now wrapped individually in aluminum foil, then baked for two hours in a dedicated store oven. FamilyMart says this retains moisture, producing a soft, sticky texture and dessert-like sweetness. Japanese-grown varieties include Beni Haruka, Silk Sweet and Beni Masari, depending on the region and season, stored for roughly a month after harvest to develop their sweetness.

The foil also keeps the potatoes in good eating condition for longer, extending their selling window and helping reduce food waste, according to the company. Eligible yakiimo will be ¥20 off every Friday from October 23, 2026, through May 28, 2027, subject to supplies.

Lawson Store 100 Has Its Own Sweet Potato Season

FamilyMart is not alone in bringing back the seasonal staple. Lawson Store 100 began selling its Japanese-Grown Beni Haruka Roasted Sweet Potato, Large (国産 紅はるか 焼き芋 Lサイズ), on Wednesday, October 14, 2026, for ¥214 including tax. The potatoes are roasted slowly in dedicated equipment inside the stores.

The chain says it sold more than one million roasted sweet potatoes last season, from September 2025 through May 2026. This year’s offering again centers on Beni Haruka, a variety prized for its sweetness and dense, sticky flesh.

There is an introductory offer, too. Purchases of a large roasted sweet potato through Tuesday, October 20, 2026, earn a receipt coupon for ¥50 off the same product on a subsequent purchase. Coupons can be redeemed through Tuesday, October 27, 2026. The offer is specific to Lawson Store 100; it does not apply at regular Lawson or Natural Lawson stores. Availability and prices may vary by location.

Spot the Sweet Potato

The hunt need not stop at the konbini. Yakiimo also turn up at supermarkets, neighborhood greengrocers and roaming sweet potato trucks. In convenience stores and supermarkets, look for a dedicated roasting oven, with the potatoes kept warm in a glass-fronted display case or under heat lamps. Out on the street, you may hear a truck’s drawn-out “yaaaaki-imooo” call before you see it.

If you’re in Japan this winter, put a little sweet potato spotting on the itinerary. Your cold hands—and your appetite—will thank you.