What does “Buy to Close” mean?
When you Sell to Open an option, you create a short option position. You receive premium, but you also accept an obligation.
A Buy to Close order buys back that same option contract and closes the obligation.
Simple mental model:
Sell to Open = create an obligation and collect premium.
Buy to Close = pay to remove that obligation.
Sell to Open = create an obligation and collect premium.
Buy to Close = pay to remove that obligation.
Where Buy to Close is used
| Original Position | Opening Order | Closing Order | What You Are Closing |
|---|---|---|---|
| Covered Call | Sell to Open Call | Buy to Close Call | Your obligation to sell shares at the call strike |
| Cash-Secured Put | Sell to Open Put | Buy to Close Put | Your obligation to buy shares at the put strike |
| Naked Call | Sell to Open Call | Buy to Close Call | Uncovered obligation to deliver shares |
| Short Put | Sell to Open Put | Buy to Close Put | Obligation to buy shares |
Covered Call example
Assume you own 100 shares of MCD and sell one call.
| Step | Action | Option Price | Cash Flow |
|---|---|---|---|
| 1 | Sell to Open 1 MCD $300 Call | $4.00 | +$400 received |
| 2 | Later: Buy to Close same MCD $300 Call | $1.00 | -$100 paid |
Option profit = Premium received - Cost to buy back
$400 - $100 = $300 profit before fees and taxes
After Buy to Close, the call position is gone. You keep your 100 MCD shares,
and you no longer have an obligation from that call to sell them at $300.
Cash-Secured Put example
Suppose you want to buy MCD at a lower price and sell a cash-secured put.
| Step | Action | Option Price | Cash Flow |
|---|---|---|---|
| 1 | Sell to Open 1 MCD $270 Put | $3.00 | +$300 received |
| 2 | Later: Buy to Close same MCD $270 Put | $0.75 | -$75 paid |
$300 - $75 = $225 option profit before fees and taxes
Once the put is closed, you no longer have the option obligation to buy 100 MCD shares at $270.
Your broker can generally release the cash or buying power that was reserved for that put.
Why would you Buy to Close?
1
Lock in profit
The option has lost most of its value and you do not want to wait until expiration.
2
Avoid assignment
The stock is approaching or passing your strike and you no longer want the assignment outcome.
3
Free capital
Closing a cash-secured put may release cash or buying power for another trade.
4
Change your view
Your market outlook changed and you want to remove the original position.
5
Manage event risk
Earnings, dividends, or other events are approaching and you do not want the exposure.
6
Prepare to roll
You close the existing option and open another strike or expiration.
Profit or loss when buying to close
| Situation | Original Premium | Buy-to-Close Cost | Result |
|---|---|---|---|
| Option loses value | $4.00 | $1.00 | +$3.00/share profit |
| Option expires near worthless | $4.00 | $0.10 | +$3.90/share profit |
| Option becomes more expensive | $4.00 | $6.00 | -$2.00/share loss |
| Option becomes much more expensive | $4.00 | $10.00 | -$6.00/share loss |
Short Option Profit/Loss = Premium Received - Cost to Buy to Close
Important: Buy to Close can produce a loss
Many beginners assume that because they received premium when selling the option, they will always make money.
That is not true. If the option rises in value, buying it back can cost more than the premium you originally received.
Example: You sell a call for $2.00 and later buy it back for $7.00.
You received $200 and paid $700 to close.
Your option loss is approximately $500.
You received $200 and paid $700 to close.
Your option loss is approximately $500.
Buy to Close vs. letting the option expire
| Choice | Advantages | Disadvantages |
|---|---|---|
| Buy to Close | Removes assignment risk, locks in P/L, frees capital, lets you immediately use shares or cash elsewhere. | Requires paying remaining option value and possibly trading fees/spread. |
| Let Expire | No closing trade needed; you may keep the entire premium if it expires worthless. | Assignment risk remains until expiration and small remaining premium may not justify the risk. |
A common management approach: close after most profit is earned
Suppose you sold an option for $5.00.
| Current Option Price | Profit Captured | Remaining Potential Profit |
|---|---|---|
| $2.50 | $250 = 50% | $250 |
| $1.25 | $375 = 75% | $125 |
| $0.50 | $450 = 90% | $50 |
| $0.10 | $490 = 98% | $10 |
Once most of the premium has already been earned, an investor may decide that the small remaining profit
is not worth continuing to carry assignment or event risk. There is no universal percentage that is right for everyone.
Covered Call: when Buy to Close can be especially useful
| Situation | Possible Reason to Buy to Close |
|---|---|
| Stock rises rapidly toward call strike | You have changed your mind and want to keep the shares. |
| Call becomes deeply in the money | You want to remove assignment risk, though buying it back may be expensive. |
| Ex-dividend date approaches | Early assignment risk may become more relevant for an in-the-money short call. |
| Option value falls near zero | You may close cheaply and write another call. |
| You want to sell the stock now | Closing the call first removes the obligation attached to those shares. |
Cash-Secured Put: when Buy to Close can be especially useful
| Situation | Possible Reason to Buy to Close |
|---|---|
| Stock rises well above put strike | The put may become cheap; close it and release reserved cash. |
| Stock falls sharply | You no longer want to buy the shares at the strike. |
| Your view of the company changes | You can remove the obligation before assignment. |
| You need the reserved cash | Closing the put may free the collateral. |
| Most premium has already been earned | Close and potentially deploy capital into a new trade. |
What is rolling?
A roll usually means closing the current short option and opening another option, often with a different strike, expiration, or both.
Step 1: Buy to Close
Close the existing short call or short put.
Step 2: Sell to Open
Open a new call or put with a different strike and/or expiration.
Example: Buy to Close an October $300 call and Sell to Open a December $310 call.
This is commonly described as rolling the call “out and up.”
Buy to Close is not the same as Buy to Open
| Order | What It Does | Position After Trade |
|---|---|---|
| Buy to Open | Buys a new call or put | You now own a long option |
| Buy to Close | Buys back an option you previously sold | Your short option is reduced or eliminated |
| Sell to Open | Creates a new short option position | You receive premium and accept an obligation |
| Sell to Close | Sells an option you previously bought | Your long option is reduced or eliminated |
The four option order actions
| Action | Meaning | Typical Cash Flow |
|---|---|---|
| Buy to Open | Create a long option position | Pay premium |
| Sell to Close | Exit a long option position | Receive option sale proceeds |
| Sell to Open | Create a short option position | Receive premium |
| Buy to Close | Exit a short option position | Pay to buy the option back |
Memory shortcut:
Open = create a position.
Close = remove a position.
Buy = pay premium.
Sell = receive premium.
Open = create a position.
Close = remove a position.
Buy = pay premium.
Sell = receive premium.
Beginner checklist before Buy to Close
| Check | Question |
|---|---|
| ☐ Correct contract | Am I closing the same ticker, call/put, strike, and expiration that I sold? |
| ☐ Quantity | Am I closing the correct number of contracts? |
| ☐ Profit/loss | What did I receive originally, and what will it cost to close now? |
| ☐ Assignment risk | Is the option in the money or near expiration? |
| ☐ Bid/ask spread | Is the option liquid enough to close at a reasonable price? |
| ☐ Next step | Am I closing permanently or rolling to another option? |
| ☐ Taxes | What realized gain or loss will closing create? |
Key takeaway
Sell to Open → Buy to Close
If you sold an option and later want to eliminate that short position, Buy to Close is the normal closing order.
You may buy it back for less than you received and realize a profit, or you may have to pay more than you originally received and realize a loss.
Short Option P/L = Premium Received - Buy-to-Close Cost