Business Forms in Japan — Overview

Japan offers several legal forms for doing business, available to both foreigners and Japanese nationals. A sole proprietorship (個人事業主, kojin jigyo) is an individual conducting business; legally it is not separate from the person, so liability is always personal and unlimited — the owner is liable for business debts with all personal assets. In exchange, a sole proprietor can engage in almost any activity (unlike a corporation, which is limited to what is written in its articles of incorporation), and all profit is automatically treated as the owner's personal income. Bookkeeping is simpler: cash-basis accounting (income minus expenses equals profit) is allowed, whereas a corporation must keep double-entry books (複式簿記). The Business Manager visa does not accept a sole proprietorship — it requires a corporation (KK or GK). The two main corporate forms are 合同会社 (GK, Godo Kaisha), an LLC-like entity with limited liability, a simple and cheap set of articles, and minimal bureaucracy, and 株式会社 (KK, Kabushiki Kaisha), a joint-stock company: more complex to set up but more familiar and "solid"-looking to Japanese partners and investors. 有限会社 (YK) is an obsolete form — no new YK companies have been registered since the 2006 reform, and legally it is equivalent to GK, though companies that were registered as YK earlier keep that designation. Other forms encountered in practice include a branch or representative office of a foreign company, the nonprofit 一般社団法人, and holding-company structures. See: KK vs GK — Detailed Comparison. The key differences between a sole proprietorship and a corporation: liability is personal and unlimited for a sole proprietor versus limited to the company's capital/assets for a corporation; a sole proprietor can pursue almost any activity while a corporation is restricted to what its articles of incorporation state; a sole proprietor's profit automatically becomes personal income, while a corporation's money does not belong directly to the director without a formal process (salary, dividends); bookkeeping is simpler for a sole proprietor (cash basis) versus mandatory double-entry for a corporation; the Business Manager visa works only with a corporation; and registration is a simple, often optional notice (開業届) for a sole proprietor versus formal registration with the Legal Affairs Bureau (法務局, Homukyoku) for a corporation. Registering as a sole proprietor via the 開業届 notice is legally optional: one can operate and declare income as an individual without filing it, and there is no penalty for not filing. If a sole proprietor's annual income is below 200,000 yen, filing a tax return can be skipped entirely, and the activity can easily be suspended. The upside of filing is access to blue-form (青色申告) deductions and the ability to deduct business expenses — without filing, business expenses cannot be deducted. The downside: filing the 開業届 disqualifies the person from unemployment insurance (雇用保険) benefits after leaving a previous job (if they were paying into it, they must formally opt out), and can create obstacles for certain child-support benefits. Registering a sole proprietorship should therefore be a deliberate decision, not something done "just in case." The threshold beyond which incorporating becomes more tax-efficient than staying a sole proprietor is loosely put at around 9 million yen of annual income — a very rough estimate that depends heavily on the structure of expenses and salaries (unconfirmed, chat opinion). A common pattern is to start as a sole proprietor and convert to a corporation once that threshold is crossed, using a separate conversion procedure. A sole proprietor can deduct up to 1 million yen per year for a spouse treated as a dependent, tax-free, if the spouse has no other income. A sole proprietor can open a bank account under their own name plus a 屋号 (trade nickname), producing a "pseudo-corporate" account that contains both the person's name and the business name. A personal account can technically also be used for sole-proprietor transactions (this is legally allowed), but banks may freeze the account if they see suspicious activity: occasional freelance work with a few transfers a month is usually fine, while a large number of clients or foreign-currency transfers is safer handled through a dedicated account. From an existing work visa it is theoretically possible to switch to working for one's own sole proprietorship and renew the work visa through it, but this needs a long-term contract with a real client inside Japan willing to submit information about itself to immigration (unconfirmed chat opinion).