> ## Documentation Index
> Fetch the complete documentation index at: https://docs-polymarket-us.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Fractional Contracts

> Learn why Polymarket US only supports whole contracts and does not offer fractional contracts

Polymarket US does not support fractional contracts. All trades are executed in **whole event contracts**.

## How It Works

When you buy using a dollar amount, the system purchases as many whole contracts as that amount can buy at the current market price.

Any remaining amount that is not enough to buy a full contract returns to your cash balance.

## Example

You want to spend 100 dollars to buy Yes contracts priced at **\$0.65**:

* Each contract costs **\$0.65**
* 100 ÷ 0.65 = **153.84 contracts**
* You receive **153 whole contracts** for \$99.45
* The remaining **\$0.55** returns instantly to your cash balance

Only whole contracts are purchased. No fractional amounts are created.

## Key Points

* Polymarket US only supports **whole contracts**
* When buying with a dollar amount, you receive the maximum number of whole contracts available at the current price
* Any unused amount that cannot buy a full contract returns immediately to your cash balance