Your Bar-Close EA Still Needs 24/7 Uptime: What Actually Happens When the Terminal Is Offline

A tempting piece of logic: "my EA only trades on bar close, so it checks the market once an hour — surely it does not need to run around the clock." The logic is wrong, and the ways it is wrong are worth understanding before they cost you money.

An EA is not lodged at the broker. It is code running inside your terminal, and when the terminal is off, nothing of the EA exists anywhere. Positions stay open, hard stop-loss and take-profit orders stored on the server still work — but everything the EA itself does is suspended: no new entries, no exits on signal, no trailing, no breakeven moves, no basket management.

If the terminal is offline at the close that carried an entry signal, most well-written EAs will not backfill it — the moment has passed and the next bar is a different decision. You silently skip a trade the backtest counted. Worse is the exit side: a bar-close exit signal that fires into a dead terminal leaves the position open until you reconnect, holding through market moves the strategy explicitly wanted to avoid. And a trailing stop is not an order at all until the EA moves it; server-side the stop sits at its last modified price, so a trend that runs during your downtime gives back profit the trail would have locked in. The entry rule needing one tick per hour does not mean the position management does.

For bar-close systems with stops well away from the market, low ping to the broker is largely a vanity metric — a signal executed 80 milliseconds later is the same trade. What matters is boring reliability: does the machine stay up for months, restart cleanly after host maintenance, and relaunch the terminal automatically. Buy uptime first; buy latency only if you run a strategy that actually needs it, which bar-close trend following does not. A home PC with sleep disabled fails this test more often than people expect — Windows updates alone will reboot it at the worst possible time.

After any restart, planned or not, check four things: the terminal is connected (bottom-right traffic indicator, not just the window being open); the EA is attached with algorithmic trading enabled — this toggle silently resets in some update scenarios; the Experts log shows the EA initialising without errors; and open positions still match what the EA expects to manage. Two minutes of checking beats discovering a week later that the EA had been a chart decoration.

A portfolio EA we run this way ourselves, 24/7 on an always-on machine: https://www.mql5.com/en/market/product/182751

All products and free utilities: https://www.mql5.com/en/users/app.develop.sk/seller