Covered Call Screener Filters: What to Look For to Find the Best Trades

The Short Answer: Six Filters That Do the Heavy Lifting

The best covered call screener filters are implied volatility rank (IVR), delta, bid-ask spread, open interest, days to expiration (DTE), and stock liquidity. Run those six filters together and you cut a universe of thousands of optionable stocks down to a short list of trades worth pricing. Everything else — earnings dates, dividend schedules, sector exposure — is a secondary check you do after the first pass.

Filter 1: Implied Volatility Rank (IVR) — The Most Important Number

IVR tells you how expensive today's options are compared with the past 52 weeks. A reading of 0 means IV is at its yearly low; 100 means it is at its yearly high. When you sell a covered call, you want to collect as much premium as possible, so you want IVR to be elevated — not rock-bottom.

A practical starting range is IVR between 30 and 60. Below 30, premiums are thin and you are giving away your upside for very little. Above 60, something is usually wrong with the stock — an earnings report is imminent, a lawsuit just dropped, or the sector is in freefall. Those situations carry real assignment and gap-down risk that can wipe out weeks of premium in one session.

The CBOE publishes educational material on how implied volatility is calculated from options prices. Their VIX methodology white paper is a useful reference if you want to understand the math behind IV. For covered call screening purposes, just remember: IVR between 30 and 60 is your sweet spot.

Filter 2: Delta — How to Pick the Right Strike

Delta measures how much an option's price moves for every one-dollar move in the stock. For covered calls, delta also approximates the probability that the option expires in the money and you get assigned. A call with a delta of 0.30 has roughly a 30% chance of expiring in the money.

Most income-focused covered call sellers target a delta between 0.20 and 0.35. That range gives you a meaningful premium while keeping assignment probability manageable. Sellers who want to hold their shares long-term lean toward 0.20. Sellers who are comfortable being called away — or who bought the stock specifically to sell calls against it — can go up to 0.40.

The Options Industry Council (OIC) explains delta in detail in its free options education curriculum. Their definition is the standard one used across US and Canadian retail brokerage platforms.

Filter 3: Bid-Ask Spread and Open Interest — Liquidity Is Non-Negotiable

A wide bid-ask spread is a hidden tax. If the bid on a call is $1.00 and the ask is $1.60, you will likely fill somewhere in the middle — but in a slow market you might get stuck near the bid. That $0.30 to $0.60 slippage can eat a large share of your premium on a low-priced stock.

Set your screener to flag options where the bid-ask spread is no wider than $0.10 to $0.15 on options priced under $1.00, or no wider than 5% of the midpoint on higher-priced options. Pair that with an open interest filter of at least 500 contracts at the specific strike you are targeting. High open interest means market makers are active and fills are faster.

FINRA has published investor guidance noting that illiquid options markets can result in unfavorable execution prices. That guidance applies directly here: thin options on small-cap or thinly traded stocks are where retail sellers get hurt most on entry and exit.

Filter 4: Days to Expiration — Why 21 to 45 DTE Is the Standard Window

Theta — the daily time-decay dollar amount — accelerates as expiration approaches. The steepest part of that curve runs from about 45 days out to expiration. Selling in the 21-to-45 DTE window lets you capture that accelerating decay while still collecting a premium worth the trade.

Options expiring in fewer than 14 days carry more gamma risk: a sharp move in the stock can flip an out-of-the-money call in the money very quickly, and you have little time to react. Options expiring beyond 60 days tie up your shares for a long time and expose you to more stock-price risk for a premium that does not scale proportionally with time.

For most retail covered call sellers, the monthly expiration cycle (roughly 30 DTE) is the practical default. Weekly expirations are available on high-volume names like AAPL, SPY, and NVDA, but they require more active management and generate more taxable events — a point the IRS and CRA both care about when you are tracking short-term capital gains on expired or bought-back options.

A Worked Example: Screening and Pricing a Covered Call on AAPL

Suppose AAPL is trading at $213.50. You already own 100 shares. You open your screener and run the six filters.

IVR check: AAPL's IVR is 38 — inside the 30-to-60 target range. Premium is elevated but not crisis-elevated. Green light.

Delta and strike selection: You want a delta near 0.25. The $220 call expiring in 32 days shows a delta of 0.24. That strike is about 3% out of the money. Green light.

Bid-ask spread: The $220 call has a bid of $2.15 and an ask of $2.25. The spread is $0.10 — tight and liquid. Green light.

Open interest: The $220 strike for that expiration shows 12,400 contracts of open interest. Well above the 500-contract minimum. Green light.

DTE: 32 days — inside the 21-to-45 window. Green light.

Premium math: You sell one contract (100 shares) at the $2.20 midpoint. You collect $220 in premium. Your effective downside buffer is $220 divided by $21,350 cost basis — about 1.03% of protection. Your maximum gain if assigned at $220 is ($220 - $213.50) × 100 + $220 premium = $870 on the position, or roughly 4.1% in 32 days.

All five filters passed. This is the kind of trade a screener is designed to surface quickly.

Risks You Need to See Clearly Before You Screen

Covered calls are not a free-money strategy. The OIC and SEC both classify them as a moderately complex options strategy that requires approval from your broker. Here are the real risks, stated plainly.

Capped upside: If AAPL jumps from $213.50 to $235 before expiration, you are called away at $220. You miss $15 per share of gains. That is the core trade-off every time you sell a call.

Stock decline is not fully hedged: The $220 premium you collected covers only $2.20 of a potential drop. If AAPL falls to $190, you still lose $23.50 per share minus the $2.20 premium — a net loss of $21.30 per share. Selling covered calls reduces your cost basis slightly; it does not protect you from a serious drawdown.

Early assignment: American-style options (the standard type on US stocks) can be assigned before expiration. This is most likely to happen just before an ex-dividend date. If you are assigned early, you lose the shares and any upcoming dividend. Check the dividend calendar before selling.

Tax treatment: In the US, the IRS treats premiums received from selling covered calls as short-term capital gains in most cases. If the call is a qualified covered call under IRS rules, the holding period of your underlying shares may be suspended while the call is open — which can affect long-term capital gains treatment. In Canada, the CRA has its own rules on option premiums and adjusted cost base. Consult a tax professional for your specific situation.

Secondary Filters Worth Adding After the First Pass

Once your six core filters return a short list, run these secondary checks before placing the trade.

Earnings date: Never sell a covered call that spans an earnings announcement unless you understand and accept the volatility risk. IV typically spikes before earnings and collapses after — the so-called IV crush. If you sell before earnings and the stock gaps up 15%, you are capped at your strike. If it gaps down 15%, your premium barely dents the loss.

Ex-dividend date: As noted above, calls sold on dividend-paying stocks near the ex-date carry early assignment risk. Either close the call before the ex-date or choose a strike far enough out of the money that early exercise is unlikely to be profitable for the call buyer.

Sector concentration: If your portfolio already has heavy tech exposure, screening for more NVDA or MSFT covered calls adds correlated risk. A good screener lets you filter by sector so you can diversify your income stream.

Stock trend: Selling covered calls on a stock in a confirmed downtrend means you are collecting small premiums while the stock erodes your capital. Many experienced sellers use a simple 50-day or 200-day moving average filter to avoid selling calls on stocks already in a downtrend.

What is the most important filter in a covered call screener?

Implied volatility rank (IVR) is the single most important filter because it tells you whether you are being paid fairly for the risk you are taking. An IVR between 30 and 60 generally means premiums are elevated enough to be worth selling without signaling a crisis in the stock. Without checking IVR first, you can easily sell calls for pennies when the market is calm and miss the best opportunities.

What delta should I use when screening for covered calls?

Most retail covered call sellers target a delta between 0.20 and 0.35, which translates to roughly a 20% to 35% probability of the call expiring in the money. A delta near 0.20 favors keeping your shares; a delta near 0.35 collects more premium but increases the chance of assignment. The Options Industry Council (OIC) explains delta in its free education resources if you want a deeper breakdown.

How do I know if a covered call option is liquid enough to trade?

Check two numbers: the bid-ask spread and open interest at your target strike. A spread of $0.10 or less on options priced under $1.00 is a good benchmark, and you want at least 500 contracts of open interest at that specific strike. FINRA has noted that illiquid options markets can lead to poor fill prices, so skipping the liquidity check is a common and costly mistake for retail sellers.

How many days to expiration should I target when selling covered calls?

The 21-to-45 days-to-expiration (DTE) window is the standard range because theta decay accelerates most sharply during that period. Most income sellers default to the monthly expiration cycle at around 30 DTE. Going shorter than 21 DTE increases gamma risk, meaning a quick move in the stock can push your call in the money faster than you can react.

Should I avoid selling covered calls before earnings?

Yes, in most cases you should avoid selling a covered call that spans an earnings announcement unless you fully understand the risk. Implied volatility spikes before earnings and collapses after, which can work against you if the stock moves sharply in either direction. If the stock gaps up past your strike, your gains are capped; if it gaps down, the small premium you collected barely offsets the loss.

Are covered call premiums taxed as income or capital gains?

In the US, the IRS generally treats premiums from selling covered calls as short-term capital gains, not ordinary income, when the option expires or is bought back. However, if the call is not a qualified covered call under IRS rules, it can suspend the holding period of your underlying shares and affect long-term capital gains treatment. Canadian investors should check CRA guidance on option premiums and adjusted cost base, and both groups should consult a tax professional for their specific situation.