Position Sizing for Options: How Much Should You Risk Per Trade?
Position sizing is the most important risk management skill in options trading — and the one that gets the least attention. You can have a 40% win rate and still grow your account consistently if your winners are sized correctly relative to your losers. You can have a 70% win rate and blow your account if you're over-sizing losers.
The Core Principle: Fixed Fractional Sizing
The most robust position sizing approach for options traders is fixed fractional sizing — risking a fixed percentage of your account on each trade.
Our recommended maximum: risk no more than 5% of your total account on any single trade.
For options, "risk" = the total premium paid (your maximum loss if the option expires worthless).
| Account Size | 5% Risk Per Trade | What That Buys |
|---|---|---|
| $1,000 | $50 | 1 contract at $0.50 premium |
| $2,500 | $125 | 1–2 contracts at $0.75–$1.25 |
| $5,000 | $250 | 2–3 contracts at $0.95–$1.25 |
| $10,000 | $500 | 3–5 contracts at $1.00–$1.50 |
| $25,000 | $1,250 | 5–10 contracts at $1.25–$2.50 |
At 5% per trade, you can absorb 10 consecutive losing trades and still have 60% of your account intact. That's the resilience you need to survive the inevitable losing streaks.
Scaling Into High-Conviction Trades
Not all setups are created equal. TarsierAlpha's Entry Score system reflects this — an 85/100 setup deserves more capital than a 63/100 setup.
A reasonable scaling framework:
| Entry Score | Position Size | Rationale |
|---|---|---|
| 62–69 (C) | 3% of account | Moderate conviction, smaller bet |
| 70–79 (B) | 5% of account | Good setup, standard sizing |
| 80+ (A) | 7–8% of account | High conviction, larger position |
Never exceed 10% on a single position regardless of conviction. Overconfidence is the precursor to account-destroying losses.
The Minimum Viable Contract Rule
At TarsierAlpha, we have one hard rule around position sizing that overrides percentage-based calculations: if your account can afford at least 1 contract, the trade is valid.
Refusing a legitimate setup because "1 contract only represents 0.8% of my portfolio" is overly conservative. A single contract is still real money, real experience, and real P&L. Take the trade with 1 contract rather than skipping it entirely.
Laddering: Sizing Your Exits, Not Just Your Entries
Position sizing isn't just about how much you put in — it's about how you take money out. TarsierAlpha uses a laddering exit strategy:
- Sell 1/3 of position at Target 1 (first resistance or +50–80% options gain)
- Sell 1/3 of position at Target 2 (+100–150% options gain or midpoint of gap)
- Let final 1/3 ride with house money to maximum target
The laddering approach accomplishes two things: it locks in real profit so a reversal can't turn a winner into a loser, and it keeps you in the trade for the full potential move. This is how a +100% trade becomes a +200% trade — because you still had a third of your position when the big move came.
The Kelly Criterion (Advanced)
For mathematically inclined traders, the Kelly Criterion is a formula for optimal position sizing:
Kelly % = Win Rate − [(1 − Win Rate) / Win/Loss Ratio]
With TarsierAlpha's current 50% win rate and approximate 3:1 average win/loss ratio:
Kelly % = 0.50 − [(0.50) / 3.0] = 0.50 − 0.167 = 33.3%
The full Kelly suggests 33% per trade — which is far too aggressive for most traders. The standard practice is to use half Kelly or quarter Kelly to account for estimation error and variance.
Half Kelly here = 16.5%. Quarter Kelly = 8.25%.
These are theoretical maximums, not recommendations. For most retail traders, the simple 5% rule produces better long-term results because it prevents the psychological devastation of large drawdowns.