Enter the total monetary amount invested in a mutual fund and the total number of shares owned to calculate the average cost basis.

## Average Cost Basis Formula

The following formula is used to calculate an average cost basis.

ACB = TI / S

- Where ACB is the average cost basis
- TI is the total amount invested in the mutual fund
- S is the total number of shares owned

## Average Cost Basis Definition

An average cost basis is defined as the average cost of a fund or stock per share of the fund owned. That is the amount you paid per share on average.

## Average Cost Basis Example

How to calculate an average cost basis?

**First, determine the total amount invested.**Calculate the total amount invested over time.

**Next, determine the number of shares.**Calculate the total number of shares currently owned.

**Finally, calculate the average cost basis.**Using the equation above, calculate the average cost basis.

## FAQ

**What is a cost basis?**

A cost basis is defined as the total cost including fees that was used to purchase a security.