Theta, and the word income
Theta is the amount an option price falls per day if nothing else changes. The UBER $72.50 call decays at $3.45 a day per contract at 42 days out. As a seller you collect that, which is why premium selling gets described as income, and why that description causes more damage than any other idea in options.
Theta is real. The framing around it is the problem.
The number
Short one October 17 $72.50 call on UBER, 42 days out, collected for $153.
Theta is -$0.0345 per share, so $3.45 per contract per day. The minus sign is from the option owner's perspective: they lose it, you gain it. Hold the position a week with the stock exactly where it is and the contract falls from $153 to about $128.
That is $25 for doing nothing, on $6,840 of stock. Annualize it and it looks wonderful, and every options marketing page in existence stops right here.
The condition nobody reads
If nothing else changes. Theta is a partial derivative. It holds the stock still, holds volatility still, and asks what one day of the calendar is worth on its own.
Nothing else stays still. Here is the same position seven days later, four ways.
| UBER at | Option worth | Your P/L | Theta said |
|---|---|---|---|
| $68.40 (unchanged) | $128 | +$25 | +$24 |
| $66.00 (down 3.5%) | $68 | +$85 | +$24 |
| $70.50 (up 3.1%) | $205 | -$52 | +$24 |
| $72.00 (up 5.3%) | $275 | -$122 | +$24 |
Theta predicted $24 in every row. The actual outcomes span $207. On a 5.3 percent move in a stock that runs at 32 percent volatility, which is an unremarkable week, the theta was noise.
Theta is not what you earn. It is the small steady tailwind under a position whose result is decided by the stock.
Why "income" is the wrong word
Income is what a bond coupon does. It arrives, it is yours, and the arrival does not depend on anything.
Theta is not delivered. It is the gradual expiry of a liability you are still carrying. Until the contract is closed or expires you owe an obligation that can grow faster than the decay shrinks it, and calling the decay income encourages exactly the behaviour that blows accounts up: selling more contracts to raise the daily figure, which raises the obligation in the same proportion.
A better sentence, and one that survives a bad month: you are being paid a rent for holding a risk, and theta is the rate the rent accrues.
Where theta comes from
An option price is intrinsic value plus extrinsic value. Intrinsic is what it would be worth exercised right now, and it does not decay at all. Extrinsic is everything else, and it goes to exactly zero at expiry.
Our $72.50 call is out of the money, so all $153 is extrinsic and all of it is going to zero, one way or another. Theta is the schedule of that trip.
Two things set the pace. Volatility, because a higher implied volatility means more extrinsic value to shed. And moneyness, because at-the-money contracts hold the most extrinsic value of any strike, which means they have the most to lose per day.
The part that surprises people
Theta is not constant, and it does not simply grow as expiry approaches. On this out-of-the-money call, theta rises from $3.45 a day at 42 days to a peak near $4.32 around 14 days, and then falls to six cents on the final day.
An at-the-money contract does the opposite and accelerates the whole way to $23.24 a day. Same stock, same expiry, opposite shapes. That contrast is its own page, and it decides when to close a position.
Both curves walked through on video, using this chain (6:37 on YouTube).
Three practical reads
- Compare theta against the position, not the credit. $3.45 a day on $6,840 of committed capital is 0.05 percent a day. That is the honest denominator.
- Never chase theta with contract count. Doubling the position doubles theta and doubles the gap risk. The ratio is unchanged and the sizing is now worse.
- A high theta is a warning as much as a feature. The contracts with the fattest daily decay are at-the-money and near-dated, which is also where gamma is at its worst. You are not being handed decay for free.
OptionsKing scores every candidate strike on a deterministic 0 to 100 scale, blends that score with the return on the capital the trade ties up, and shows you the highest-ranked handful. There is no minimum score. How it works covers what the ranking does and does not tell you.
Questions people actually ask
What is theta in options?
The amount an option price falls per day from time passing alone, holding the stock and volatility fixed. The UBER $72.50 call decayed at $3.45 per contract per day with 42 days to expiry.
Is theta the same as income?
No, and the word does real damage. Theta is a partial derivative that assumes nothing else moves, and over one ordinary week the same position ranged from plus $85 to minus $122 against a theta prediction of $24 in every case.
Does theta increase as expiration approaches?
For at-the-money options yes, sharply. For out-of-the-money options it peaks a couple of weeks out and then collapses toward zero, because a strike that will not be reached stops having extrinsic value to lose.
How do I collect theta?
By being short the option and having the stock cooperate. The decay only becomes money when you close the position or it expires, and until then the obligation you sold can grow faster than the decay shrinks it.
Sources
Rules and thresholds above were checked against these documents on August 4, 2026. Exchange and broker rules change. Confirm anything you are about to act on with your own broker.
Keep reading
Do the math on your own trade
Every price in this article is an illustrative worked example, not a quote. Read The Greeks for the rest of the series, and the disclaimer before you act on any of it. Selling options carries real risk of loss, and the loss can be far larger than the premium you collected.