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DTE (days to expiry), explained for sellers

DTE means days to expiry, the number of days left on the option you sold. It decides how fast the premium melts, how much room the stock has to move against you, and when it's worth getting out.

Options guide · 8-minute read · Updated 2026-10-26

What DTE means

DTE is days to expiry, counted in calendar days. A put that expires in 30 days has a DTE of 30. Tomorrow it has 29. It drops by one every day, weekends included, and the option's time value drops with it.

For a seller, DTE is the length of the promise. Sell a 45-DTE put and you're on the hook for 45 days unless you buy it back. The longer the promise, the more premium you collect, and the more time the stock has to go wrong.

The curve, and why it isn't a straight line

Time value doesn't melt evenly. Far from expiry, each day takes a small bite. Near expiry, each day takes a bigger one. The Theta of the option, its daily melt, grows as DTE shrinks.

Here's a hypothetical chain for one strike at different DTEs, with the melt per day worked out.

Read the third column. The 7-day option melts more than twice as fast per day as the 45-day one. That's the appeal of short expiries. Now read the second column. The 7-day option pays $50 for a week of risk; the 45-day pays $120 for six weeks. Same strike, same stock.

Why many sellers open around 30 to 45 days

Three reasons, all trade-offs rather than rules:

• Enough premium to be worth the risk. At 30 to 45 DTE the cushion is meaningful. At 7 DTE a $0.50 premium moves your break-even by fifty cents.
• The melt is already decent. The curve starts bending faster somewhere around 30 to 45 days, so you collect a good share of the total melt without holding to the end.
• Room to be wrong. A stock that dips in week one and recovers by week five is a non-event at 45 DTE. At 7 DTE, the same dip is assignment.

The other half of the wheel strategy works the same way. A covered call at 30 to 45 DTE collects a fair premium and leaves time for the stock to drift. 30 DTE vs 45 DTE compares the two most common choices.

The 21-day idea

Many sellers don't hold to expiry. They open at 45 DTE and close or roll at about 21 DTE, whatever the stock has done.

The thinking: by 21 DTE, a 45-day option that's gone well has lost most of its value, so there's little left to collect. What remains is the risky part of the curve, where a sudden move hits the option hardest. Taking the money and starting a fresh 45-day trade resets the clock with more cushion.

If the trade has gone badly, 21 DTE is also a decision point. Roll out to a later month, take the assignment, or close for a loss. Our guide on when to roll vs take assignment walks through that choice. Either way, the point is to decide on purpose, not to wake up on expiry Friday with the stock sitting on your strike.

A worked example (an illustration, not a trade idea)

A made-up stock, XYZ, trades at $50. You sell one $45 put at 45 DTE for $1.20. You collect $120 and set aside $4,500. Your break-even is $43.80.

Path A, the quiet path. XYZ drifts to $51. At 21 DTE the put is worth about $0.35. You buy it back for $35. You keep $85 and open a new 45-day trade with the clock reset.

Path B, the bad path. XYZ falls to $44 by 21 DTE. The put is now worth about $1.90. Your choices:

Notice that the 21-day rule doesn't save the trade. Closing locks in −$70. Rolling extends the promise. Holding leaves the bottom rows on the table. DTE management decides when you face the question. The stock decides the answer.

Short DTE, the fine print

Weekly and 0-to-7-day options tempt sellers because the melt per day is highest. Three things to know before going there:

• The premium is thin, so the cushion is thin. A $0.50 premium on a $45 put means the stock only has to close at $44.50 for you to lose.
• Every move is magnified. Near expiry, an option near the strike flips from worthless to fully in the money on a small move. That jumpiness is called gamma, and the Greeks for the wheel explains why sellers of short options feel it most.
• More cycles, more spread. Fifty-two weekly trades cross the bid-ask spread fifty-two times. How the bid-ask spread taxes option sellers shows what that costs.

7 DTE vs 30 DTE puts the two side by side.

Try it on paper: pick one stock and one strike, and write down the premium at 7, 14, 30 and 45 DTE from the Options chain. Divide each by its DTE. You'll see the curve in your own numbers. Theta decay explained covers the melt in more depth, and the options math cheat sheet has the formula.

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