There is currently no concept of “Doing Business As” in Singapore where a trade name or fictitious business name, under which the business or operation is conducted and presented to the world is not the legal name of the business or legal person(s) who actually owns the business and is responsible for it. If you would like to conduct or operate your business using a trade name you can either incorporate/register another company/business using the trade name or you can register a trademark for the trade name. If the trade name is not registered, it cannot be used for any official documents including opening of bank account, issuing of invoices, application of licences, etc. All official documents including invoices of a company/business must contains the Company/Business Name and the Registration Number.