Position Sizing for Funded Accounts: Size to the Drawdown, Not the Balance

A $50,000 funded futures account and a $50,000 personal brokerage account look identical on the balance line, but they are not the same account to size positions against. A personal account's only real constraint is your own risk tolerance. A funded account has a hard, external constraint — the drawdown floor — and it doesn't move just because your balance grows. Sizing to the balance instead of the drawdown is one of the more common, quietly fatal mistakes on a funded account.

The number that actually matters

On a funded evaluation or funded account, the number that ends your account isn't your balance hitting zero — it's your balance (or, on trailing-drawdown firms, your equity) crossing a specific dollar floor well above zero. A $50,000 account with a $2,000 maximum drawdown doesn't have $50,000 of room to be wrong — it has $2,000. Every position-sizing decision should reference that $2,000, not the $50,000 headline balance, because the $2,000 is the actual distance between trading and not trading anymore.

Fixed risk per trade

A workable starting framework is to risk a small, fixed percentage of the remaining drawdown allowance on any single trade — not a fixed percentage of account balance. If your firm's drawdown is $2,000 and you cap risk at 5% of that per trade, you're risking $100 per trade, which means it takes a string of consecutive losing trades, not one bad trade, to meaningfully threaten the floor. As the drawdown floor changes (rising with a trailing-drawdown account, or staying fixed under EOD or static drawdown), recalculate the dollar risk against the current floor distance, not the original one.

Contract and micro math

Once you know your dollar risk per trade, converting it to a contract size is arithmetic: divide your per-trade dollar risk by the dollar value of your stop distance in that instrument. A stop 10 points away on an instrument worth $50 per point per contract is a $500 risk per contract — if your per-trade risk budget is $100, that's a fifth of a contract, which isn't tradable on a standard-size contract. This is exactly the situation micro contracts exist for: at one-tenth the point value of the standard contract, the same $500-per-point-of-stop math becomes $50 per contract, making a $100 risk budget tradable as two micros instead of forcing you into an oversized standard contract just because it's the only unit available.

• Calculate position size from your stop distance and dollar risk budget, in that order — never pick a contract size first and then figure out where the stop has to go to make it fit.
• Re-run the math per instrument and per setup — a stop that's appropriately sized on one instrument or timeframe can be wildly oversized or undersized on another at the same contract count.
• Widen the buffer, don't just narrow the stop, when the math doesn't fit cleanly — an artificially tight stop to make a bigger contract size work just moves the risk from position size onto get-stopped-out frequency.

Why aggression underperforms survival here

It's tempting to size up on a funded account because the capital isn't personally at risk in the same way — a breach costs the evaluation or reset fee, not the account balance. But that framing misses the actual payoff structure: a funded account only pays out over time, through repeated profit splits, and a single breach ends that stream completely. A trader sizing conservatively enough to survive a bad month, even at a slower pace, generates far more expected value across a year of funded trading than one who sizes aggressively and has a meaningful chance of ending the account in month one.

This is a risk-management framework, not a guarantee — futures trading carries real risk of loss regardless of how carefully a position is sized, and disciplined sizing reduces the odds of a breach without eliminating market risk. This is not financial advice.

Rebuilding the numbers as the drawdown floor moves

On a trailing-drawdown account, the floor moves up every time you set a new equity high, which means the dollar distance between your current balance and the floor isn't fixed for the life of the account the way it is under EOD or static drawdown. A trader who calculates position size once, at the start of an evaluation, and never revisits it can end up either overexposed relative to a floor that's crept closer, or unnecessarily conservative relative to one that's moved further away. Treat the drawdown-room calculation as something to re-check periodically, not a one-time setup step, especially after a stretch of strong or weak trading that would have shifted the floor meaningfully.