Stock split definition

A stock split is a corporate action that increases a company's share count by dividing each existing share into several, while lowering the share price in the same proportion. The total value of the company, and of your holding, stays the same.

The company sets a ratio, such as 4-for-1 or 2-for-1, and every shareholder receives the extra shares automatically. Market capitalisation does not change, because the lower price exactly offsets the higher share count. Companies usually split to bring a high share price down to a more accessible level, which can widen the pool of potential buyers and improve liquidity.

A stock split is the opposite of a reverse split. A reverse split consolidates shares, for example turning ten shares into one and raising the price tenfold, often to lift a low price back above an exchange's minimum. Neither action changes the underlying value of what you own; both only change the number of shares and the price per share.

Stock split Example

You hold 1 share priced at USD 100 when the company runs a 4-for-1 stock split. Your single share becomes four, and the price divides by four:

USD 100 √∑ 4 = USD 25

You now hold 4 shares at USD 25 each. Your total value is unchanged:

4 √ó USD 25 = USD 100