Value-date holidays and surprise swap charges

[Shadow Trader]

Sometimes a swap charge appears that doesn't match anything on the swap table. A position held across a holiday gets charged for extra days, or for a day that wasn't expected.

The reason is the value date. Spot trades settle two business days later, and a holiday in either currency's country pushes that date out. The swap covers the extra days. If the Japanese market is closed for Golden Week, a USDJPY position held over rollover may carry the swap for three or four days instead of one.

Brokers usually publish calendars of the days when triple swaps apply, but not always clearly. Some apply the charge to every pair the same way, regardless of the holidays in each country. Others adjust pair by pair.

For scalpers, this rarely matters, because positions don't stay open that long. But for anyone testing a longer-held setup or running a bot that sometimes carries trades overnight, a spreadsheet of expected swap versus actual swap reveals mismatches.

A mismatch isn't automatically a broker error. It may simply be a holiday nobody noticed.

What was behind the last swap charge that looked wrong on a statement?