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Option chain columns that matter to sellers

An options chain shows a dozen columns, and most of them are noise for a seller. Five tell you what you'll collect, whether you can get out, how likely assignment is, whether the premium is rich, and how long you're on the hook.

Options guide · 7-minute read · Updated 2026-10-26

The five columns, and what each one answers

Open any Options chain and you'll see strikes down the middle, calls on one side, puts on the other, and columns of numbers. For a seller, these five do almost all the work.

Everything else on the screen is either derived from these, or matters to buyers and spread traders more than to someone running the wheel strategy.

Bid and ask, the only prices that count

The bid is what you'll get if you sell right now. The ask is what you'd pay to buy back right now. The mid sits between them.

Read the spread as a share of the mid. A $0.95 / $1.05 quote is a 10% spread on a $1.00 option. A $0.80 / $1.20 quote is 40%. The second one costs you four times as much every time you trade it. Reading an options quote goes through each number on the line, and the mid price shows how to fill near the middle.

Ignore last. It's the price of the most recent trade, which could be from this morning on a quiet strike. Ignore change for the same reason.

Open interest and volume, your exit

Open interest is the number of contracts open at that strike and expiry. Volume is how many traded today. OI tells you whether there's a market to close into next week. Volume tells you whether there's one today.

A simple screen: OI in the hundreds at your strike, and a spread under about 10% of the mid. If both fail, the chain is telling you that closing or rolling will be expensive. Low OI also means the bid you see may be a placeholder, not a real buyer. The Open interest term page has more.

Delta, the rough odds

Delta has two meanings and sellers use the second. It's how much the option moves per $1 move in the stock, and it's also a rough estimate of the chance the option finishes in the money.

A put with a 0.25 delta is, roughly, expected to finish in the money about one time in four. That's the same as saying there's about a one-in-four chance of Assignment, give or take. It's a rule of thumb, not a promise, and it assumes the market's pricing is about right.

Most sellers pick a delta range first, then look at the strike that lands there. Delta for option sellers explains the number; the Greeks for the wheel covers the two others worth knowing.

IV and DTE, how rich the premium is and for how long

IV, or Implied volatility, is the market's guess at how much the stock will move, baked into the premium. Higher IV, bigger premium.

The trap is comparing IV across stocks. A 60% IV on a biotech is low for it; a 30% IV on a utility is high for it. Compare the number with the stock's own range over the past year. Many chains show an IV rank or IV percentile that does this for you. A rank near the top of the range means the premium is fat because the market expects a big move, often an earnings report. Check the date before you sell.

DTE is days to expiry. Some chains show the date; some show the count. Either way, it sets how long the stock has to move against you and how fast the option's value melts. DTE explained for sellers covers the curve. The short version: many sellers open around 30 to 45 days and manage at about 21.

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

A made-up stock, XYZ, trades at $50. Here's a slice of its put chain, 30 days out, with the columns that matter and nothing else.

Reading down: the $45 put has a 0.24 delta, a tight spread, and the deepest OI. The $42 put has a 40% spread on a $0.50 mid and thin OI. The $48 put pays the most and has the highest odds of assignment. You pick the $45 and collect about $100, working the order near the mid.

Here's the one thing the chain never shows: what happens next.

The 0.24 delta said assignment was roughly a one-in-four shot. It didn't say the stock would stop at $45 if it came. The chain picks the trade. The chart and your sizing decide whether you can afford the bottom row.

Columns you can leave alone, for now

• Theoretical price / model price. A calculation, not a quote. Trade the bid and ask.
• Gamma, vega, rho. Real, but not the first thing a seller of 30-day options needs. The Greeks for the wheel says when they matter.
• Intrinsic / extrinsic. Useful once you're deciding whether to close early. Not needed to open.
• Probability ITM / probability of touch. Derived from delta and IV. Fine to glance at, but delta already told you.
• Last, change, % change. Stale on anything but the busiest strikes.

Set up your broker's chain to show bid, ask, OI, delta and IV, and hide the rest. A screen with five columns makes better decisions than a screen with fifteen. Then run the five-question check from how to read an options chain before every trade.

Questions