Keeping a Second Currency From Quietly Costing You Money

If you get paid in one currency and spend in another (freelancing for overseas clients, or living somewhere different from where your income originates), the exchange rate you see quoted usually isn't the real cost. The bigger cost is usually frequency: converting a little bit every time money arrives, instead of larger amounts less often.

Why batching conversions actually saves money

Every conversion, no matter the amount, typically carries a spread (the gap between the buy and sell rate) plus sometimes a flat wire fee. Say that combined cost is roughly 1.5% per conversion, plus a flat $5 fee. Converting $200 four times a month costs 4 times ($5 plus 1.5% of $200), which is 4 times ($5 plus $3) equals $32 a month. Converting the same total $800 once a month costs one $5 fee plus 1.5% of $800, which is $5 plus $12, equals $17. Same total amount moved, nearly half the cost, purely from batching instead of converting on arrival.

Tracking it without losing the real number

The practical problem this creates for tracking: if you convert on arrival, your local-currency ledger shows a slightly different amount every time for what was actually the same foreign-currency income, which makes it hard to tell if your income actually changed or the exchange rate just moved. Expentify keeps one currency for the whole ledger, so the simplest approach is to log foreign income at the amount you actually received after converting, on the day you convert. Batching conversions also means fewer, larger entries, which makes month-to-month income easier to compare.

This doesn't eliminate currency risk. If the exchange rate moves against you while you're holding a balance to batch-convert later, that's a real tradeoff against the fee savings above, worth weighing against how volatile the specific currency pair actually is.