DTE · expiry
The days until the option expires. More time costs more, but gives the idea time to work and loses less value per day.
The trade-off: time against cost
More days to expiry make an option more expensive, but each day costs less and the idea has time to work. Fewer days are cheaper in dollars, but theta eats the premium faster and the stock has to move quickly.
For a fictional at-the-money call on a $100 stock with IV of 30 %: with 45 days left it costs about $4.44 and loses about $0.05 a day; with 14 days left it costs about $2.42 but loses about $0.09 a day, over twice as much relative to its price.
How to choose expiry for a long option
- Estimate how long the move needs. A trend continuation over several weeks needs a different expiry than a quick rebound.
- Add buffer. Choose an expiry clearly later than the planned exit, so you sell before the steep part of time decay.
- Check events. If earnings fall before expiry, decide on purpose whether to hold through them.
The screener applies this with fixed windows: swing setups use 30 to 45 DTE, short-term setups 14 to 18 DTE (the next Friday expiry with at least 14 days left), reversal setups 10 to 15 DTE. Long options are closed by 7 DTE at the latest.
Common mistakes
- Matching expiry exactly to the expected move. If the move comes a week late, the option has already lost most of its time value.
- Choosing by price alone. The cheapest expiry is often the one with the worst odds.
Frequently asked questions
What is the best DTE for buying calls?
It depends on the idea. For moves over several weeks, 30 to 45 days is a common range because time decay is still moderate. Very short expiries need the move to come almost immediately.
When should I sell a long option before expiry?
Many traders exit well before the final week, because time decay accelerates there. The screener's rule closes long options by 7 days to expiry.
See it in the screener
The live demo shows every term with example data, right next to the score and its reasons.