The daily time decay of an option's value — the silent tax on every long option.
Theta measures how much value an option loses per day as expiration approaches, all else equal. It's the price of time: a long option is a wasting asset, and theta is the burn rate. The decay accelerates into expiration — an option loses value slowly with 60 days out and violently in the final week. For buyers, theta is the enemy: your directional read has to be right AND timely. For sellers, theta is the paycheck. This is why LA Traders-style options entries happen at the Retrace — you want the move now, not eventually, because the clock is literally costing you money.
Every day you hold a long option, the market collects rent. Theta is why 'I'll wait and see' is a losing options strategy.
Your SPY put has −0.08 theta. Every day that passes costs you $8 per contract, move or no move. Three days of chop = $24 gone before the trade even starts.
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