What it means
An options contract gives its buyer the right, but not the obligation, to buy or sell an asset at a set price before a set date. When you sell to open, you are the one granting that right.
You collect the premium immediately and agree to honour the contract if the buyer exercises it. This is different from sell to close, where you sell a contract you already own to end your position.
The order type matters because it tells the broker whether you are creating a new position or closing an old one. Choosing the wrong one can open a position you never intended.
Investors use sell to open to earn income. A holder of shares might sell call options against them, collecting premium and accepting that the shares may be sold at the strike price.
Another investor might sell put options and agree to buy shares at a chosen price, which brings in premium while they wait. The risk is that the seller keeps only the premium in the best case but can face large losses in the worst.
A seller of a put loses if the price falls well below the strike, and a seller of an uncovered call can face very large losses if the price rises sharply. Brokers therefore require approval levels and collateral for these trades.
For a finance reader, the main points are that the premium is income only if the contract expires or is bought back at a profit. Taxes, margin requirements and assignment risk (being required to buy or sell without warning) also apply.
Always understand the maximum possible loss before trading. Tax treatment and account rules add another layer.
Premium received is not always taxed in the way ordinary income is, and the rules differ by country and by type of account. Anyone using the strategy should check the tax and broker rules before placing the first trade.
In practice
Real-world examples.
Example
A retiree owns 1,000 shares of a utility company and sells to open 10 call contracts above the current price. She collects premium each month, which adds to her dividend income. If the shares rise above the strike, she accepts that they will be sold.
Example
A private investor wants to buy a stock at a lower price and sells to open put contracts at that price. If the stock drops, he buys it at his chosen level. If it does not, he keeps the premium. In either case he has set his buying price in advance.
Example
A treasury analyst at a small manufacturing company notes that the firm's brokerage policy forbids selling options. The sell to open order would create a short position that carries potentially unlimited loss, which the board has not approved. She flags the request to the audit committee instead of placing the order.
Formula
Calculation
Premium received = number of contracts x shares per contract x premium per share
Suppose an investor sells to open 5 put contracts with a $50 strike at a premium of $2.40 per share. Each contract covers 100 shares, so the premium received is 5 x 100 x 2.40 = $1,200. If the shares fall and she is assigned, she must buy 500 shares at $50, costing 500 x 50 = $25,000. Her net cost is 25,000 - 1,200 = $23,800, which is 23,800 / 500 = $47.60 per share.Case study
Seen in the real world.
Cedar Falls Family Office is an illustrative, fictional investment vehicle managing $2,000,000 for a single family. The manager started selling to open covered calls on shares the family already held and earned about $4,000 a month in premium.
In one month, a takeover bid sent a share price far above the strike. The shares were called away at the lower strike, so the family missed much of the jump.
The manager explained the trade-off and kept selling calls but chose strikes further from the current price. The illustrative lesson is that premium income comes with a capped upside. The family now treats the premium as a fee for giving up some potential gain, not as a free extra.
Watch out
Common mistakes.
- Treating the premium as free money when the seller has taken on a real obligation that can cost far more than the premium.
- Mixing up sell to open with sell to close and entering the wrong order.
- Selling uncovered calls without understanding that the potential loss is not limited.
Questions
People also ask.
What does it mean to be assigned?
Assignment is when the buyer exercises the option and the seller is required to deliver or buy the shares at the strike price.
Is sell to open the same as shorting a stock?
It creates a short position, but in a contract rather than in the shares, and the risks and rewards are different.
Can I close a sell to open position early?
Yes, by buying the same contract back, which is called a buy to close, and the profit or loss is the difference in premium.
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