Which pair moves first? Lead and lag in the majors

[Fairman]

Which pair moves first? Lead and lag in the majors

When news hits the dollar, not every pair reacts at the same instant. Some move a fraction of a second earlier. Others follow.

EURUSD, being the most liquid, often leads. GBPUSD and AUDUSD tend to follow within a few hundred milliseconds. Crosses, built from the legs, lag more. In the yen space, USDJPY often responds to moves in US yields before other pairs register anything.

These lags are tiny and mostly irrelevant for manual trading. For systems running on fast feeds, the lead-lag relationship offers a possible edge, and also a warning. A signal on a lagging pair can be stale at the time it fires.

Some scalpers watch the leading pair as a confirmation. If EURUSD has already moved, a trade on GBPUSD in the same direction is entering late.

The relationships change with the news. In a UK data release, GBP pairs lead. In US data, EURUSD leads.

Testing involves recording ticks on several pairs and cross-correlating returns at different lags. The result shows how many milliseconds separate the moves.

Does the pair being traded tend to lead or follow, and does that change by session or news type?

[Shadow Trader]

Two pairs share the dollar as one leg and tend to move together. When news hits, EURUSD often reacts a touch earlier, with GBPUSD following. The lag is brief, from a few hundred milliseconds to a couple of seconds, and it comes and goes.

The logic is liquidity. EURUSD is the most traded pair, so information gets reflected there first. Related pairs adjust as dealers update their own quotes and arbitrage keeps relationships tight.

A scalper watching both charts might see GBPUSD catching up after a sharp move in EURUSD. In theory, it's a signal. In practice, the window is tiny, and by the time a human sees, decides, and clicks, the catch-up is done. Spreads on the lagging pair can also widen at exactly that moment.

The relationship is also unstable. It breaks down when the news is specific to one economy. A UK data release moves GBPUSD first, with EURUSD barely noticing.

Using the pair as context rather than as a trigger is more realistic. If EURUSD has just jumped and GBPUSD hasn't, something is about to adjust.

One caveat is that such lags shrink when volatility spikes. In a fast market, quotes update so rapidly that the lag disappears, and the pairs move almost in lockstep. In a quiet market, the lag may be larger but the move is small. The sweet spot, if there is one, is narrow.

Could the lag between related pairs ever pay for itself, or is it only useful as context?