AMD sells off for three sessions, stabilizes around a level it has bounced from twice before, and you think the worst of it is over. You don't need a rally. You just need the stock to stop falling. That's the setup a put credit spread was built for: you sell a put below the market, buy a cheaper put further below it for protection, and keep the difference if price stays above your short strike. It's one of the first defined-risk trades worth learning once you've outgrown single-leg buying, and it sits near the center of the options strategy toolkit.
The same trade goes by two names. "Put credit spread" describes the cash flow — you receive a credit when you open it. "Bull put spread" describes the bias — you want the underlying to rise, or at least hold. Same two legs, same risk profile, different emphasis.
How a put credit spread works
A put credit spread has exactly two legs, both puts, both on the same underlying, both expiring on the same date:
- Sell one put at the higher strike (the short leg, closer to the money)
- Buy one put at the lower strike (the long leg, further out of the money)
The put you sell is worth more than the put you buy, so the position opens for a net credit. That credit is the most you can make. The gap between the strikes, minus the credit, is the most you can lose. Selling a put obligates you to buy shares at the strike if you're assigned, which is why the long put underneath matters — it caps what that obligation can cost you, and understanding how calls and puts behave in opposite directions makes clear why the lower strike acts as a floor rather than a second bet.
Because both legs are puts in the same quantity with the same expiration, this is a vertical spread — one of the simplest multi-leg structures there is.
A worked example
Say AMD is trading at $160 and you expect it to hold above $150 over the next month. You open a spread 30 days out:
Leg | Action | Strike | Premium |
|---|---|---|---|
Short put | Sell to open | $150 | $3.10 credit |
Long put | Buy to open | $145 | $1.70 debit |
Net | $5 wide | $1.40 credit |
One spread covers 100 shares, so the numbers per spread are:
- Credit received: $1.40 × 100 = $140
- Width of strikes: $150 − $145 = $5, or $500
- Max loss: $500 − $140 = $360
- Breakeven: $150 − $1.40 = $148.60
- Max profit: $140, kept if AMD closes above $150 at expiration
Three outcomes at expiration. Above $150, both puts expire worthless and you keep the full $140. Below $145, both puts are in the money, the spread is worth its full $5 width, and you lose $360. Between $148.60 and $150 you still come out ahead, just not by the full credit — the short put has some intrinsic value, but less than the credit you collected.
Notice the risk-to-reward: you're risking $360 to make $140. That's typical for credit spreads and it's the trade-off at the heart of the strategy. You win more often than you lose, but each loss is bigger than each win. Where you place the short strike controls that ratio directly, and getting it right matters more than almost anything else in the trade — everything in a guide to choosing a strike applies here twice over, once per leg.
Why sell a spread instead of a naked put
Selling a put on its own collects more premium. It also leaves you exposed all the way down toward zero, and your broker will hold collateral accordingly. Buying the lower put gives up part of the credit in exchange for three things: a known worst case, far less capital tied up, and no scenario where a gap down turns a modest position into a serious problem.
The mirror image on the call side works the same way. A bear call spread pairs a short call with a long call above it, collecting a credit and profiting if the underlying stays below the short strike. Put credit spreads express a bullish-to-neutral view; call credit spreads express a bearish-to-neutral one.
Premium selling with built-in protection is the same instinct behind a covered call, except the protection there comes from owning shares rather than from a long option. In both cases you're paid up front and the structure decides in advance how bad the worst day can get.
Credit spreads also combine. Sell a put spread below the market and a call spread above it in the same expiration and you've built an iron condor, a range trade made of two credit spreads that pays as long as price stays between the short strikes.
What makes the spread gain or lose value
Three forces move a put credit spread, and the Greeks name all of them.
Direction (delta). A short put carries positive delta and the long put carries negative delta, but the short leg sits closer to the money, so the net position is positive-delta — it gains as the underlying rises. The further price climbs above your short strike, the less direction matters, because the spread is already approaching worthless.
Time (theta). Positive theta is the engine. Every day that passes with price above the short strike drains value from the spread you sold, letting you buy it back for less than you received. Decay accelerates into the final weeks, and because the options Greeks interact differently as expiration nears, a spread that behaved calmly at 40 days can swing hard at four.
Volatility (vega). The position is short vega. You collect a fatter credit when implied volatility is elevated, and the spread loses value — in your favor — when volatility cools off afterward. Selling put spreads into a panic in a crypto-linked name like COIN, or after an earnings-driven spike in META, is the classic application, as long as you accept that rich premium usually means the market has a reason to be nervous.
Choosing strikes and width
Two decisions define the trade:
- Where to place the short put. Delta works as shorthand: a 30-delta short put sits closer to the money, pays a bigger credit, and has a rough 30% chance of finishing in the money. A 15-delta short put pays less and expires worthless more often. Technical levels do the same job — prior support, a moving average, the low of a recent range.
- How far apart the strikes sit. A $5-wide spread risks $500 per contract before the credit; a $1-wide spread on QQQ risks $100. Narrow spreads let you size precisely and keep individual losses small, while wide spreads collect more per contract and concentrate risk.
A reasonable rule of thumb: aim to collect roughly a third of the width as credit. On a $5-wide spread, that's about $1.65. Collect much less and the risk-to-reward turns ugly; demand much more and your short strike ends up uncomfortably close to the money.
Managing the position
Credit spreads reward decisiveness more than patience. A few habits that hold up:
- Take profits early. Buying the spread back at 50% to 75% of the maximum credit removes the tail risk of the last stretch, where gamma is highest and one bad session can erase weeks of decay.
- Set a loss point before you open. A common one is closing when the spread's value reaches twice the credit received — roughly a $280 loss on a $140 credit, well short of the $360 maximum.
- Decide what happens if price reaches the short strike. Close, roll down and out for a further credit, or hold because the thesis is intact. Choose in advance, not while you're watching it breach.
- Respect expiration week. The spread's value starts swinging wildly on small price moves, and holding a tested spread into the final session is a coin flip rather than a strategy.
Rolling deserves one caution. Pushing a losing spread out in time for an extra credit feels like a save, but it keeps a losing position alive and often turns one defined loss into a larger one across several rolls. Roll only when you'd genuinely open the new spread fresh today. Otherwise, close it.
Assignment and expiration risk
Your short put can be assigned at any time, since US equity options are American-style. In practice, early assignment becomes likely only when the short put is deep in the money with little time value left, and the OCC's reference on options assignment notes that the risk climbs as an option moves deeper in the money and as expiration approaches. If you are assigned, you buy 100 shares at the short strike and still hold the long put, so the loss stays capped — but you now have a share position to deal with.
The uglier scenario is pin risk at expiration: the underlying settles between your strikes, the short put is assigned, the long put expires worthless, and you're holding stock over the weekend. Closing before expiration avoids it entirely, which is the simplest argument for banking profits early.
Put credit spreads at a prop firm
Not every funded account permits them, because credit spreads require selling to open and many options evaluations don't allow that at all. At Vanquish, vertical credit spreads are available on the Advanced Options plan, alongside iron condors, straddles and covered calls. The other plans are limited to buying calls and puts.
One structural difference reshapes the strategy there: every position closes by 3:59 p.m. ET, so a credit spread becomes a same-day trade rather than a 30-day theta grind. That means shorter-dated spreads, short strikes placed further out, and decay measured in hours — much the way 0DTE options traders already handle the structure.
FAQs
Is a put credit spread the same as a bull put spread?
Yes. The two names describe one position from different angles — one names the credit you receive, the other names the bullish bias. You'll also see "short put spread" and "put vertical" used for the same two legs.
What happens if the stock finishes between the two strikes?
The short put finishes in the money and the long put expires worthless. The spread's value at expiration equals the short strike minus the settlement price, capped at the width. If that value is less than the credit you collected, you're still profitable. Above breakeven you keep part of the credit; below it you take a partial loss.
How much collateral does a put credit spread require?
Brokers typically hold the width of the spread minus the credit received, which is also your maximum loss. That's far less than the cash-secured requirement for selling the same put on its own, and it's one of the main attractions of the structure.
How many days to expiration should I use?
Premium sellers often favor 20 to 45 days, where decay is meaningful without the violent gamma of expiration week, then close at a profit target instead of holding to the end. Shorter-dated spreads decay faster but leave almost no room to manage a position that turns against you.
Can a put credit spread lose more than its maximum loss?
Not as long as both legs share the same quantity and expiration and you don't close the long put while the short put is still open. Legging out — taking off the protection and leaving the short put naked — removes the cap, and that's where traders get hurt.
The appeal of a put credit spread is that it pays you for being approximately right. You don't need to call the bottom, catch a rally, or nail the timing; you need the underlying to stay above a level you chose. The price of that comfort is an unflattering risk-to-reward ratio, which only works if you cut losing spreads before they reach the maximum and take profits well before expiration week.
Defined-risk credit trades belong alongside the rest of the options strategies worth keeping in rotation, and they combine neatly with the directional trades you probably run already.
The deeper lesson carries further: the credit you collect is the market's price for a risk you've agreed to carry, and that same logic — premium, decay, volatility — shows up in nearly every options structure you'll trade next.
Trading spreads in an evaluation means finding one that actually permits selling to open, so it's worth comparing what each Vanquish plan allows before you pick one.
