How to know if someone is a millionaire
One measurement is the total value of all property owned by a household minus the household's debts.
A household owning an £850k home, £30k of furnishings, two cars worth £35k, a £35k retirement savings account, £25k in mutual funds, and a £175k holiday home with a £100k mortgage, £30k in car loans, and £12k in credit card debt would be worth £1,080k and every individual in this household would therefore be a millionaire.
However, according to the net financial assets measurement, equity in someone's principal residence is excluded, as are lifestyle assets, such as the car and furniture. Therefore the above example household would only have net financial assets of £48,000 plus possibly the equity in the holiday home of £75,000.
Another term used is "net investable assets" or "working capital". They may use the term "millionaire" to mean somebody who is available to invest a million units of currency through them as broker. For similar reasons, those who market goods, services, and investments to high net worth individuals are careful to specify a net worth "not counting principal residence." Many other specific definitions can be used, but essentially a millionaire is seen to be somebody in a household with a net worth of one million units.