Some contracts have a tick size that changes when the front month changes. So, there is one tick size for the front contract and a different tick size for future contracts.
Other contracts have a tick size that changes according to price level. So, there is one tick size when the premium is under 5 and a different tick size when the premium is greater than 5 for the same contract. For EP options, the tick for prices less than or equal to the premium of 5 is 2.5. Prices over the premium of 5 have a 12.5 tick.
DOMTrader, Order Ticket, and Order Ticker all display variable tick sizes. Orders must be at a tradable price. When a stop limit order is modified, the price slippage between stop and limit prices is kept. If the resulting limit price becomes non-tradable, it is rounded to the nearest tradable price. If the rounded price equals the stop price, a single tick slippage between stop and limit prices of the modified order is set.
All contracts in a spread have to use the same tick size, so be aware of variable tick size when trading intracommodity spreads. To look up the tick value of a contract, use Contract Specifications (CSpec). Variable tick sizes are listed in the Tick Value field. Hovering the mouse over those values provides a tooltip.
In this example, the tick for the front month is 6.25, while the tick for contracts more than two months out from the front month is 12.5.
Variable tick size applies to both futures and options.
To display options in ticks
1. Open any options window.
2. Click Setup, then Options Preferences.
3. Click the Greeks Scale tab.
4. In the Price scale field, click Tick Units.
When displaying Gamma in ticks, if the underlying contract has different tick sizes depending on its price, the tick size used to calculate the Gamma is the maximum tick size of these tick sizes. When displaying Theta, Vega, and Rho in ticks, if the contract has different tick sizes depending on its premium, the tick size used to calculate the Gamma is the maximum tick size of these tick sizes.