Running an EA on a Prop Firm Account

A funded account is not your account, and the rules that come with it change what an EA can safely do. Here is what firms measure, where a grid strategy struggles against a hard daily limit, and the arithmetic behind the wider prop firm sizing rule.

Last updated 14 August 2026

What a prop firm is actually checking

Your contract is enforced by software watching the account every second. Know which numbers it watches.

Two firms can both advertise "5% daily" and mean different things by it. Ask in writing before you fund: balance or equity, when exactly it resets, static or trailing, grid allowed or not. Keep the reply.

Why a grid strategy is harder work on a funded account

On your own account a hedging grid carrying a floating loss is a problem only if margin runs out. The basket has time to work, and time is the strategy. Under a daily equity rule you have no time: the loss counts the moment it exists, and if it crosses the line at 14:32 the account is finished even if the basket would have closed in profit an hour later.

Forex Success AI is a grid. The relevant defaults are in the Inputs tab: Range 21, the gap in pips between levels; Level_Max 12, the most positions a basket holds before it stops adding; and DiMarti 1.7, the multiplier applied to the previous lot at each new level.

That last one is the part people miss. Fix_lot sets the first order of a basket only. Every level after it takes the last lot and multiplies. From 0.01, on a 0.01 lot step, the ladder runs:

LevelsLotsRunning total
1 to 40.01, 0.02, 0.03, 0.050.11
5 to 80.09, 0.15, 0.26, 0.441.05
9 to 120.75, 1.28, 2.18, 3.718.97

A full basket started at 0.01 holds just under 9 lots across 231 pips of grid. As the twelfth level fills, the floating loss on a major pair (at 10 USD per pip per standard lot) is roughly 2,640 USD.

Now scale it. On a 100,000 funded account the rule below gives Fix_lot 0.21, twenty-one times that basket, so the same run floats near 55,000 USD. And that is one basket: the defaults leave Buy_Counter and Sell_Counter on, two separate baskets that can build at once.

That full build-out is a tail event, but "rare" is not a risk plan when one breach ends the account. Against a tight daily limit, a martingale grid at default settings is a poor fit, and no sizing rule alone repairs that. Three things help, and all three are yours to set:

The sizing rule, and why the prop steps are wider

Set Lot_mode to Fixed and type the figure into Fix_lot. The lot size calculator gives the exact value for either setting.

On 100,000 that is 0.50 for your own money against 0.21 on a funded account, well under half the exposure per unit of balance. On your own account the binding constraint is margin and you get to wait. On a funded account it is a fixed figure someone else set, and crossing it once is terminal. It is a sizing guide, not a risk limit, and it knows nothing about your firm's numbers.

The three limits built into the EA

All three ship inactive. You switch them on in the Inputs tab.

Two mismatches to set deliberately. The EA's day rolls over at broker server midnight, your firm's at whatever its terms state, and the EA's baseline is starting equity where some firms use balance. Set the EA's percentage clearly below your firm's and treat the gap as the safety margin.

What the news filter does, and does not do

The filter downloads the ForexFactory weekly calendar and, inside a window of 120 minutes either side of a qualifying event, multiplies the grid gap by News_Gap_Multiplier (default 3.0). By default it watches high impact events for the chart symbol's two currencies only.

That is all it does. It does not stop the EA opening trades and it does not close anything before a release. It spaces the ladder out so a spike fills fewer levels. If your firm bans opening or holding through news, this will not keep you compliant: you will need to flatten and remove the EA yourself.

Copy trading and running more than one account

This catches honest people out. The same EA, same symbol, same inputs, produces near-identical entries within seconds of each other, which is exactly what copy-trading detection looks for: same instrument, same direction, same moment. Run it on a personal account and a funded account at once and expect that to be visible. Ask before, not after.

Two things that will stop the EA dead

  1. A netting MT5 account. The EA checks the margin mode on start-up and refuses to run on a netting or exchange account, because MT5 would merge the grid's opposing positions. It alerts and stops. MT4 accounts are always hedging. See hedging vs netting accounts if unsure.
  2. No Allow DLL imports. The tick box is on the Common tab. Without it the EA cannot reach the licence server, so it alerts and removes itself. The news filter needs it too: both use wininet rather than MetaTrader's WebRequest.

Run a month on the firm's demo or trial first, watching peak floating loss rather than closed profit. And nobody can tell you a particular firm permits this EA: terms differ, they change without notice, and the only version that matters is the one in your own agreement.

Where we stand

We sell software. We are not a broker, we are not regulated, we hold no client funds and we give no investment advice. Every trade happens on your own account, or on the funded account your firm gave you, under your firm's rules and your own judgement. Nothing here is a forecast of what the EA may do.

If you do buy, it is a one-time payment with a fixed number of account slots, and an unreachable licence server never closes your trades because the EA keeps retrying. The plans are here. If not, the arithmetic above holds for any grid EA you run.

Common questions

Can I use an EA on a prop firm or funded account?

Usually yes, but it depends entirely on the firm. Most allow expert advisors in principle while restricting particular behaviours: grid and martingale strategies, trading around high impact news, copying trades between accounts, and profit concentrated into a single day. Ask your firm in writing which of those apply to you and keep the reply, because terms differ between firms and are revised over time.

Why is the prop firm lot size smaller than the one for my own account?

On your own account the binding constraint is margin, so a basket carrying a floating loss has time to work. On a funded account the binding constraint is a fixed drawdown figure measured on equity, and crossing it once ends the account. The published rule therefore steps up by 0.01 for every 5,000 of balance on a prop account instead of every 2,000 on your own. On a 100,000 account that is Fix_lot 0.21 rather than 0.50, well under half the exposure per unit of balance.

Is a grid or hedging EA a good fit for a tight daily drawdown limit?

Often not, and it is worth saying plainly. With the default settings a basket adds up to twelve levels 21 pips apart, multiplying the lot by 1.7 each time, so a basket started at 0.01 can reach almost 9 lots and float around 2,640 USD before it stops adding. Scaled to a 100,000 account that arithmetic exceeds any normal daily limit, and the defaults allow a buy basket and a sell basket to build at the same time. Reducing DiMarti to 1.0, cutting Level_Max, and enabling the EA's own daily loss limit below the firm's are the practical mitigations.

Does the news filter keep me compliant with a prop firm's news trading rule?

No. The filter widens the grid gap by a multiplier, three times by default, inside a window of 120 minutes either side of a qualifying event. It does not stop the EA opening trades and it does not close open positions before a release. If your firm bans opening or holding through news, you need to flatten and remove the EA yourself around those events.

What happens if my prop firm's MT5 account is a netting account?

The EA will not run on it. On start-up it checks the account margin mode, and on a netting or exchange account it shows an alert and stops, because MT5 would merge the grid's opposing positions on the same symbol and the strategy would not function. MT4 accounts are always hedging, so the check only affects MT5.