Onigiri in Tokyo: A Guide to Japan’s Rice Balls, Fillings and Where to Try Them
Few Japanese foods are as simple as onigiri — and few are as varied. At its most basic, onigiri is simply cooked rice shaped by hand, usually with a filling inside and sometimes wrapped in nori.
Yet that simple formula has been part of Japanese food culture for centuries, evolving from a practical way to carry rice into one of Japan’s most beloved everyday foods.
Today, onigiri comes in an impressive range of styles and flavours. Traditional fillings such as umeboshi, salmon and kombu kelp remain popular, but specialist shops now offer everything from kimchi and meat to cheese and other unexpected combinations. To understand why there is so much variety, it helps to look at where onigiri came from, and how it became the food it is today.
A Brief History of Onigiri
The history of onigiri goes back around 2,000 years. Archaeologists have discovered carbonized clumps of rice at the Sugitani Chanobatake ruins in Ishikawa Prefecture, suggesting that people were already preparing rice in compact, portable portions. These early rice bundles were not quite the same as modern onigiri, but they offer an early glimpse of the idea behind the food.
Written records provide a clearer connection to today's onigiri. The Hitachi no Kuni Fudoki, compiled in the eighth century, mentions hand-formed rice known as nigiri-ii. During the Heian period, a similar food called tonjiki was eaten as a convenient meal, particularly when travelling or between events.
Onigiri gradually became an everyday food for workers, travellers and soldiers. Its practicality was part of its appeal: rice could be shaped into a compact portion that was easy to carry and eat without utensils. Nori later became closely associated with onigiri, while the Edo period saw rice balls become increasingly familiar as an everyday food.
The version most visitors recognise today was shaped further by the rise of convenience stores in the 20th century. Individually packaged triangular onigiri made rice balls even easier to buy and eat, with packaging designed to keep the nori crisp until it was opened.
But the convenience-store triangle is only one version of onigiri. Across Japan, the food has developed countless variations, with different types of rice, shapes, preparation methods, and, perhaps most importantly, fillings.
From Umeboshi to Curry: The Many Fillings of Onigiri
The filling is often what gives an onigiri its character. Some of the most traditional choices are ingredients that naturally complement rice and have long been part of Japanese food culture.
Umeboshi, or pickled plum, is one of the classics, bringing a salty, sour flavour to the rice. Salmon is another familiar favourite, while kombu (a type of kelp) provides a savoury, slightly sweet flavour. Mentaiko, tuna and bonito-based fillings are also widely found.
Many traditional fillings were practical as well as flavourful. Ingredients that could be salted, pickled, dried or otherwise preserved worked particularly well with rice, helping make onigiri a convenient meal that could be prepared in advance.
Modern onigiri shops, however, have taken the idea much further. There is no rule saying a filling has to be traditionally Japanese, and today's menus can include ingredients such as kimchi, beef, pork, cheese and curry. Some shops offer dozens of options, turning the humble rice ball into something closer to a customisable meal.
There is also a big difference in how much filling you get. Traditional-style onigiri may keep the filling tucked neatly in the centre, while modern specialist shops can be remarkably generous, with the filling almost spilling out of the rice.
For visitors, this makes onigiri particularly fun to explore. You can stick with a classic or use the enormous variety as an excuse to try something completely unfamiliar.
一汁おにぎり 一粒万福 新宿御苑店 — Ichiju Onigiri Ichiryumanpuku Shinjuku Gyoen
For a modern and minimalist take on onigiri, head to Ichiju Onigiri Ichiryumanpuku near Shinjuku Gyoen. The shop has a clean, contemporary feel that reflects the way specialist onigiri shops are elevating the food from a simple snack into a proper meal.
Its fillings have a particular emphasis on seafood, making it an interesting choice for exploring one of the most established categories of onigiri ingredients. Rather than overwhelming customers with an enormous list of unusual combinations, the focus is more on the ingredients themselves and the overall quality of the meal.
Onigiri can be enjoyed alongside soup and other dishes, giving the experience more in common with a casual Japanese set meal than grabbing a packaged rice ball from a convenience store.
It is a good example of how onigiri can be modernised without abandoning the basic appeal that has kept it popular for centuries.
おにぎり まんま — Onigiri Mamma
If you want to explore the sheer variety of modern onigiri fillings, Onigiri Mamma in Shinjuku is a particularly good place to start. The shop offers more than 50 fillings, making choosing what to order part of the experience.
There are plenty of familiar options, including salmon, ume and mentaiko, but Mamma is particularly interesting for its more unexpected combinations. Fillings include ingredients such as beef tendon, pork kimchi, natto, cheese and curry, demonstrating just how flexible the onigiri format has become.
The fillings are also generous, making these feel like substantial rice balls rather than small snacks with a little surprise hidden in the middle.
With so many options, Mamma is a great place to experiment. Try one classic filling alongside something more unusual, and it becomes easy to appreciate just how much the filling can change the character of an otherwise simple combination of rice and seasoning.
おにぎり戸越屋 渋谷道玄坂店 — Togoshiya Onigiri Shibuya Dogenzaka
Togoshiya offers another extensive selection, with around 40 varieties, but its range is more heavily focused on familiar Japanese flavours. This makes it a good choice for visitors who want plenty of options without going too far outside the classics.
You will find well-known fillings such as salmon and mentaiko alongside a broad selection of other savoury combinations. The result is a menu that feels varied without being intimidating for someone trying specialist onigiri for the first time.
Togoshiya also puts plenty of attention into the rice itself. Its rice comes from Yamagata, while carefully selected salt and nori are used in the preparation. The onigiri are made to order, so they arrive with soft, warm rice — something that makes a noticeable difference compared with packaged convenience-store versions.
It is a good reminder that a great onigiri is not only about what you put inside. The rice, nori, and seasoning (and sides!) are just as important to the final result.
おむすび横丁【東京東銀座店】 — Omusubi Yokocho Higashi Ginza
For a quieter, more local experience, seek out Omusubi Yokocho in Higashi Ginza. Compared with Tokyo's larger and more widely known onigiri specialists, this is a more understated option, with the feel of a neighbourhood spot rather than a destination food shop.
The focus here is on the everyday appeal of onigiri: well-prepared rice, a satisfying filling and a simple meal that does not require much fuss. Lunch sets are also available, making it an easy choice for a casual midday stop.
That makes Omusubi Yokocho an interesting contrast to shops such as Mamma, where choosing from dozens of fillings is part of the fun. Here, the appeal is closer to the traditional role of onigiri in Japanese food culture.
For travellers interested in seeing how Japanese people enjoy this everyday staple, rather than only its modern interpretations, it is well worth seeking out.
A Simple Food With Endless Possibilities
For something made from such a small number of ingredients, onigiri has an impressive amount of variety. Its long history shows how useful and adaptable rice has been in Japanese cooking, while today's fillings show that the food is still evolving.Traditional combinations remain popular for a reason, but there is always room to experiment.
That balance between familiarity and creativity is what makes onigiri so enduring and why a simple rice ball can be very different from one shop to the next.
Whether filled with a slice of salted salmon, a spoonful of umeboshi, or something far more unexpected, onigiri is a small food with a surprisingly big place in Japanese food culture.
