Business name

A trade name, trading name, or business name is a pseudonym used by companies to perform their business under a name that differs from the registered, legal name of the business. In a number of countries the phrase trading as (abbreviated t/a) is used to designate trade names. In the United States, the phrase "doing business as" (abbreviated DBA, dba, d.b.a. or d/b/a) is used. That is also sometimes used in Canada; but operating as (abbreviated to o/a) and trading as (abbreviated to T/A) is the most common form.

Trade names are typically used by companies to conduct their operations under a simpler brand as opposed to using their formal name within all public communications, or when a desired name was not able to be registered by the business operator, or if that business is owned by a separate company, franchisee, or a sole proprietorship.

The distinction between a registered legal name and a "fictitious" business name or trade name is important, as businesses with the latter give no obvious indication of the true identity of the entity that is legally responsible for their operation. Fictitious business names do not create legal entities in and of themselves; they are merely names assumed by existing persons or entities. Legal agreements such as contracts are normally made under the registered legal name of the business or owner, and the legal name must be used whenever a business sues or is being sued.

In English writing, trade names are generally treated as proper nouns.

In some Canadian jurisdictions, such as Ontario, when a businessperson writes a trade name on a contract, invoice, or cheque, he or she must also add the legal name of the business.

Numbered companies will very often operate as something other than their legal name, which is unrecognizable to the public.

In Chile, a trade name is known as a nombre de fantasía ('fantasy' or 'fiction' name), and the legal name of business is called a razón social (social name).

In Japan, the word yagō (屋号) is used.

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