A consistency rule caps how much of your total profit is allowed to come from a single day, and sometimes from a single trade. If your best day makes up more than the firm's limit — often somewhere between 20% and 40% of everything you earned — the account is read as lucky rather than skilled, and your pass or your payout can be held back. It is one of the quieter rules, and one of the most common reasons a passing account still doesn't pay out.
What it is
A consistency rule sets a ceiling on the share of your profit that any one day can contribute. Firms word it in a few ways:
- Best day under a set percentage — your single most profitable day must stay below, say, 30% of total profit.
- Best trade under a set percentage — the same idea applied to one position rather than a whole day.
- A minimum number of trading days — often bolted on so you can't pass in one sitting.
Break the ceiling and you don't lose the account outright; the firm simply won't let you withdraw or progress until the numbers even out.
How it works
Best day ÷ total profit < the firm's limit
The check is a division. Take your most profitable day, divide it by your total profit, and the answer has to sit under the firm's threshold. The awkward part is that the ratio moves every time you trade. A big day early on can put you offside, and the only way back is to keep grinding profit on other days until that day's share falls under the line. You can't undo a good day, so the rule effectively forces you to keep trading past the point you'd otherwise stop — which is exactly what a firm wanting proof of a repeatable edge is after.
A worked example
Say the target is £8,000 on a £100,000 account and the consistency limit is 30%. You make £5,000 on one strong Tuesday and £3,000 across the rest of the month. Total profit £8,000 — target hit. But that Tuesday is 5,000 ÷ 8,000 = 62.5% of your profit, more than double the ceiling. The firm holds the account. To fix it, your best day has to fall under 30% of the total, so £5,000 needs a total above roughly £16,700. You'd have to earn another £8,700 on other days, none of them beating £5,000, before you could withdraw a penny. One big win has quietly cost you weeks.
Why firms use it
The rule exists to filter out luck. A trader who lands their whole target on one news spike, and a martingale EA that scrapes one enormous recovery before it would have blown the account, produce the same tidy number as a steady, skilled trader. On paper they're identical. The consistency check pulls them apart. It also caps the firm's own risk: they would rather back an edge that turns up most days than a strategy that needs one heroic trade to work, because the second kind tends to fail spectacularly the month after they fund it.
How it catches high-variance EAs
This is where a lot of automated strategies come unstuck. Grid and martingale systems make small, frequent gains and then one large recovery trade that dwarfs everything else — precisely the profile the rule is built to reject. News EAs are the same shape: flat for days, then one violent move does all the work. Even a sound trend-follower can trip the rule when a single position runs unusually far. The strategy can be genuinely profitable and still fail, because the check isn't measuring whether you made money — it's measuring how evenly you made it.
How to trade within it
- Read the exact wording before you buy. "Best day" and "best trade" are different limits and catch different strategies.
- Size down. Smaller, steadier positions keep any single day's share of the total low.
- Don't sprint to the target. Hitting £8,000 in two days almost guarantees a breach; spreading it over more days keeps you clear.
- Track the ratio while you trade, not at month-end. Once a payout is refused, it's too late to rebalance.
- If you run a high-variance EA, accept that the rule may reject it even in a clearly winning month.
The Karnek note
Karnek shows your profit broken down day by day, so you can see whether one session is starting to dominate the total long before payout time. It also tracks your live drawdown against a limit you set and alerts you as you approach it. It reads your terminal read-only and can never place a trade or touch the account.
Written and reviewed by the Karnek Research team. Last updated August 2026.
Educational content only - not financial advice. Past performance does not predict future results. Trading carries significant risk.