Is There a Vegan Option at MOS Burger? The 2026 Answer After the Green Burger Was Discontinued

As of September 2026, exactly one burger at MOS Burger is described by the company itself as using no animal ingredients in its primary materials: the Avocado Basil Burger with rice-flour buns (¥620, tax included). The Green Burger (Teriyaki), for years the go-to answer, was discontinued on 20 May 2026. Most guides online still tell you to order it. They are out of date.

The 2026 answer: the Avocado Basil Burger with rice-flour buns

On 20 May 2026, MOS Food Services launched this burger nationwide (excluding some locations) and at MOS Cafe. The official press release describes it as "a burger made without animal ingredients in its primary raw materials, built on vegetables and grains." It costs ¥620 including tax.

It carries plant-based food certification from Plant Based Lifestyle Lab, a Japanese general incorporated association. MOS notes that this is "the second certified item among our products, following the Green Burger (Teriyaki)." That third-party layer matters: it is a different order of evidence from a staff member's best guess.

The Green Burger is gone (discontinued 20 May 2026)

This is where most visitors get stuck. The official release states plainly: "With this launch, the Green Burger (Teriyaki) will be discontinued."

The Green Burger was famous for its green bun and was the first of MOS's certified items. Its certification notice said it used no animal ingredients — "meat, fish, eggs, dairy and the like" — as primary materials, and also avoided the five pungent vegetables (gokun) excluded in some Buddhist vegetarian traditions. It also stated explicitly that "the sauce contains no animal ingredients either."

That role now belongs to the Avocado Basil Burger. Asking for a Green Burger at the counter will get you a blank look. Order by the current product name.

Swapping in a soy patty does not make a burger vegan

On the same day, MOS renewed its Soy Patty for the first time in six years and rolled it across eleven menu items. This has produced a persistent misunderstanding.

A soy patty does not make the burger plant-based. The renewed patty uses, in the company's words, "two types of plant protein derived from soy and wheat — granular and powdered — to reproduce a meat-like taste and texture." The patty itself is plant-based. But buns, sauces and toppings differ per product, and the "no animal ingredients in primary materials" design applies only to the certified items.

Worth noting for a second reason: because the new patty uses wheat-derived plant protein, it is not gluten-free. Assuming soy meat equals gluten-free is a common and costly error. See plant-based meat in Japan for the wider picture.

What to order and what to skip (as of September 2026)

MOS itself says these are not for strict vegans

Being honest about the limits is the whole job here. MOS states that its plant-based products "are not products intended for those pursuing complete vegetarianism." It gives the reason too: "the factories producing these ingredients and the stores themselves also produce and prepare products containing animal ingredients."

The new burger carries a further footnote: "some secondary ingredients include materials other than vegetables and grains." Certification covering primary materials does not extend to secondary ingredients or to shared production lines.

So the conclusion splits by why you are asking. If you eat plant-based for ethical or environmental reasons, this works. If you have an allergy or a strict religious requirement, check the allergen information in store before deciding. The same line runs through every Japanese chain — see hidden animal ingredients in Japanese food.

If there is no MOS nearby, or it is sold out

Sometimes there is no MOS at the station, and sometimes the burger is sold out. Pick your next move from the guide to vegan-friendly chain restaurants in Japan. For family restaurants, see what vegans can eat at Japanese family restaurants; for the fastest fix, the convenience-store playbook. Ordering phrases are collected in Japanese phrases for vegans.

Prices and availability reflect official information as of 4 September 2026. Menus change without notice — check the official allergen information before you go.