What is the difference between Paid in Capital and Paid up Capital?

Question

I am struggling to understand the difference between these two. They seem to mean the same thing and are used interchangeably.

Investopedia also has two different article on them.

Paid-in capital is the amount of capital "paid in" by investors during common or preferred stock issuances, including the par value of the shares themselves plus amounts in excess of par value. Paid-in capital represents the funds raised by the business through selling its equity and not from ongoing business operations.

-- Paid-In Capital

Paid-up capital is the amount of money a company has received from shareholders in exchange for shares of stock. Paid-up capital is created when a company sells its shares on the primary market directly to investors, usually through an initial public offering (IPO).

-- Paid-Up Capital

Answer 1

You have discovered one of the issues with investopedia. It isn't consistent.

There is also an article How Do Share Capital and Paid-Up Capital Differ? that contains this section (I have highlighted the important section):

Characteristics of Paid-Up Capital

Paid-up capital doesn't need to be repaid, which is a major benefit of funding business operations in this manner. Also called paid-in capital, equity capital, or contributed capital, paid-up capital is simply the total amount of money shareholders have paid for shares at the initial issuance. It does not include any amount that investors later pay to purchase shares on the open market.

There are other examples I have stumbled across over time.

I just noticed that both articles you linked to contain a video called "Paid-up Capital" and the paid-up article does say it is the same as paid-in capital.