Which prop firms work with an EA, and which quietly don't.
Almost all of them allow Expert Advisors. That tells you nothing. The rule that decides whether a strategy can survive is the drawdown type, it costs 25 percentage points, and it rarely appears on a comparison table.
Almost every prop firm allows Expert Advisors. That is not the question worth asking. The question is which ones have rules an EA can actually survive, and on that measure the field splits in a way no comparison table shows: firms with a static drawdown floor, and firms whose floor follows your equity peak.
The second group costs a multi-day strategy 25 percentage points of pass rate and more than doubles its failures. Both groups say "EAs allowed" on the website.
The three rules that decide everything
1. Drawdown type, and it is not on the pricing page
A static floor sits at a fixed level below your starting balance and stays there. Lose 6%, you have 4% left, and making money back moves you away from it.
A trailing floor follows your equity peak upward. Make 4%, and the floor rises 4% with you. Profit you make and then give back counts against you as if you had lost it from the start.
Some firms use an end-of-day trailing floor, which only ratchets on daily closes rather than intraday. That sits in between and is workable for most systems.
| Floor type | Passes | Blows the account |
|---|---|---|
| Static, 10% | 89.7% | 2.6% |
| Static, 6% | 85.5% | 12.3% |
| Trailing from peak, 6% | 64.5% | 35.5% |
Same target, same risk, same engine, three floors. If you hold positions overnight or across several days, this single line item matters more than the price of the challenge, the profit split, or anything else on the comparison sites.
2. The daily loss limit, against your intraday swing
A daily limit is breached by your worst point during the day, not by where you close. So the number that matters is your strategy's typical intraday excursion, not its daily result.
| Risk level | Worst intraday swing | Days beyond −3% | Beyond −4% |
|---|---|---|---|
| Conservative | −1.42% | 0 | 0 |
| Standard | −2.37% | 0 | 0 |
| Fast | −2.84% | 0 | 0 |
| Aggressive | −3.79% | 11 | 0 |
| Maximum | −4.74% | 28 | 4 |
Over 1,221 trading days. Read it as a compatibility check: a firm with a 3% daily limit is fine at Standard risk and lethal at Aggressive, where the strategy went past 3% on eleven separate days. Firms with a 5% daily limit leave room at every level.
3. Consistency rules, which are not always disclosed
Some firms cap how much of your total profit a single day may represent, often 25% to 40%. A strategy with a fat right tail can pass the target and then be told the distribution was too uneven. This is usually in the terms rather than on the sales page, and it is worth reading before you buy rather than after you pass.
The format, before the firm
Before comparing brands, compare shapes. The same engine across the four common formats:
| Format | Passes | Median time |
|---|---|---|
| One phase, 8% target, 8% static floor | 93.1% | 57 days |
| One phase, 10% target, 10% static floor | 93.3% | 55 days |
| Two phases, 8% then 5% | 91.8% | 79 days |
| Two phases, 10% then 5% (FTMO) | 89.7% | 91 days |
| Two phases, 6% then 6%, 6% floor, 3% daily | 76.9% | 66 days |
One-phase formats fund the account in roughly half the time at a slightly higher pass rate, because there is no second barrier to clear after the first one has already cost you some drawdown. If you are choosing your first challenge and the firm offers both, the one-phase version is the better arithmetic.
The bottom row shows what happens when a tight floor meets a tight daily limit: the 6/6 format with a 3% daily cap drops to 76.9% on the same engine that scores 93% one phase.
The checklist to run before you buy
Rules change often, and comparison sites go stale within weeks. Rather than trusting a table, check these nine things on the firm's own terms page on the day you buy.
| What to check | What you want |
|---|---|
| Drawdown type | static, or end-of-day trailing |
| Maximum loss | 8–10% of the starting balance |
| Daily loss limit | 5%, calculated on the day's opening balance |
| Phases | one, if the firm offers it |
| Overnight and weekend holding | allowed |
| Automated trading | allowed, with no restriction on strategy type |
| Consistency rule | absent, or above 40% |
| Reset hour of the daily limit | stated explicitly, in a named timezone |
| Copy trading across firms | check before running more than one account |
Two of these deserve extra attention because they are the ones people discover late.
Overnight and weekend holding. A firm that forces everything flat on Friday changes the strategy, not just the schedule. On our own engine, allowing weekend holds was worth 44% more profit over the same period on the same signals, because gold positions that would have been closed on Friday captured the Monday move instead.
The reset hour. The daily limit resets at a specific time in the firm's server timezone, which is frequently not your timezone and frequently not UTC. An EA that computes the day boundary wrong will breach a limit it thinks it is respecting.
If the floor follows your equity peak, we will tell you before you buy rather than after you fail. It is the single rule that decides whether a multi-day strategy has a chance, and it is the one that appears least often in comparison tables.
Which formats we recommend, and why
We are not going to publish a ranked list of brands, for a reason that is easy to verify: firms change their terms every few months, and a list like that is wrong within a season. What does not change is the shape of the rules.
Best fit
One-phase challenges with an 8–10% target and a static floor of the same size, a 5% daily limit, and overnight holding allowed. On these, the engine passes 93% of the time in roughly eight weeks, and the account is funded in half the time a two-phase challenge takes.
Workable
Two-phase challenges with 8% then 5%, static 10% floor, 5% daily. Slower at 79 days median, but the pass rate holds at 91.8% and the failure rate stays under 3%.
Use lower risk
Anything with a 4% or 3% daily limit, or a floor at 6%. Perfectly passable, but the margin for a bad day is thin and the risk level has to come down to match.
Avoid
Trailing drawdown from the equity peak, for any strategy that holds positions across days. And any firm whose terms do not state the reset hour of the daily limit, because that is a rule you cannot comply with if you cannot read it.
Does using an EA put your account at risk?
Not by itself. The firms in the workable groups above permit automated trading explicitly, and running an EA is not grounds for anything. What does cause problems, in our experience with client accounts, is more mundane:
- Two copies of the same EA on one account. Running it on a VPS and on a local terminal at the same time doubles every position. We have seen this cost a client 1,454 USD and double their drawdown before anyone noticed. A VPS does not replace your terminal, it adds one.
- Manual trades mixed in. The EA sizes positions against the account balance. Trades it did not open are invisible to it, and its risk arithmetic silently stops being correct.
- Copy trading across several firms. Many firms prohibit identical trade sequences across accounts at different companies. This is the rule that closes funded accounts most often.
- Changing the terminal timezone after setup. Every session window the strategy relies on shifts with it.
None of these is about automation being disallowed. They are about the difference between running one strategy correctly and running several things at once by accident.
Sources and limits
The pass rates on this page come from 7,000 simulated first-passage paths per configuration, built by block-resampling the daily return series of one specific engine over 1,221 trading days from January 2022 to August 2026, on 244 million real ticks. They describe how that engine behaved under those rule shapes, and they are not a forecast.
Rule descriptions are archetypes, not quotes from any particular firm. Prop firms change their terms frequently, and we have found two different versions of the same firm's published rules within the same week. Verify the current terms on the firm's own site on the day you buy.