The 4 p.m. London Fix: The Hour When Benchmarks Move Price

[Fairman]

The 4 p.m. London Fix: The Hour When Benchmarks Move Price

At 4 p.m. London time each day, a benchmark exchange rate is calculated. Many funds and corporations use it to value portfolios and settle orders, which concentrates trading around that moment.

Large orders are often executed at the fix, so that clients receive the benchmark rate. Dealers fill them by trading in the minutes before and after, and the buildup can produce sharp moves in the window around 4 p.m.

The effect is strongest at month-end, when portfolio rebalancing flows are largest, as discussed earlier. Trading around the fix has been the subject of regulatory investigations, after cases of manipulation by banks led to fines, and the methodology was changed to use a longer window and more data.

For traders, the practical points are timing and caution. Price may spike or reverse around 4 p.m. London, especially on the last trading day of the month. These moves can reverse afterward, with no lasting meaning.

If you trade intraday, check whether your stops or entries fall in this window, and consider avoiding tight stops then.

Convert 4 p.m. London time to your local time, noting daylight saving differences between London and your location.

Some traders study the behavior of their pair around the fix and build time-specific strategies, which requires careful testing.

Practical step: mark 4 p.m. London time on your intraday charts and note what price did for ten days.

[Fairman]

Quick time note for anyone in West Africa: 4pm London is 4pm in Lagos while the UK is on summer time, and 5pm in Lagos from late October to late March. Easy to get wrong the week the clocks change.

[Fairman]

The month end fix is the one I really watch. A sharp move into 4pm that has no news behind it, I don't read anything into it, and I'd rather not have a tight stop sitting nearby.