Scalping USDCHF as a mirror of EURUSD, and the days it stops mirroring

[Fairman]

Scalping USDCHF as a mirror of EURUSD, and the days it stops mirroring

A lot of scalpers treat USDCHF as EURUSD flipped upside down. Most of the time that's roughly right, because both are heavily driven by the dollar and EURCHF tends to be stable. When EURUSD rallies, USDCHF usually falls by a similar amount.

The trouble starts when EURCHF moves. If something hits the franc directly, such as a risk-off move where people buy CHF as a safe haven, or an SNB comment, USDCHF can drop while EURUSD barely moves. Anyone using EURUSD as the guide for a USDCHF trade gets caught leaning the wrong way.

So before I take a USDCHF scalp off a EURUSD signal, I glance at EURCHF. If it's flat or drifting in a small range, the mirror is probably intact. If it's moving with some purpose, I drop the mirror assumption and trade USDCHF on its own chart, or not at all.

The other practical point is that USDCHF often has a wider spread and less depth than EURUSD. If the two give you the same idea, EURUSD is usually the cheaper way to express it. I'd only pick USDCHF when its own structure is clearly better, such as a cleaner level or a stop that makes more sense.

[Fairman]

The same idea applies to any pair you're using as a proxy. GBPUSD and EURUSD move together most days, until something hits sterling directly and EURGBP takes off. AUDUSD and NZDUSD are similar. The cross between the two currencies tells you whether the relationship you're relying on is holding at that moment. I keep a small window with the relevant cross open just for this. It doesn't need analysis, just a quick look at whether it's moving. If it is, the proxy logic is off for now. On a busy morning I won't do anything fancier than that.

[Fairman]

Around risk-off moves the franc and the yen can both catch a bid at the same time, which means USDCHF and USDJPY may fall together while EURUSD does something unrelated. On those days the dollar isn't the main story, the safe haven flow is. If you're trading three dollar pairs as if they share one driver, you can end up with three positions that aren't really correlated the way you think. Checking which currency is actually moving across the board, before entering, saves a lot of confused trades. It sounds like extra work, but it's one glance at a few charts.