Why Locked Exchange Rates Beat Live Rates in Payroll
There's a tempting idea in multi-currency payroll: just pull the live exchange rate whenever you need it. It feels modern and "always accurate." In practice, it quietly makes your payroll impossible to audit and unfair to employees. Locking the rate per run is the boring choice that's actually correct.
The trouble with live rates
Exchange rates move every minute. If your payroll converts using a live rate, then the figure shown when you preview the run differs from the figure at approval, which differs again from the figure when someone re-opens the payslip next year. The same payroll period would report different numbers depending on when you looked. That's not a feature — it's a reconciliation nightmare.
Zaffre HRM captures the rate at the moment a run is finalized and locks it to that run permanently.
What locking actually buys you
- Preview, approval, and final payslip all use one consistent rate.
- Re-opening an old run reproduces the original figures, not new ones.
- Auditors can tie each net amount to a single dated rate.
- Employees see stable, explainable numbers month to month.
Imagine approving payroll at 9am, then finance re-checks at 3pm. With live rates, the totals would have drifted during the day, and someone would have to explain the gap. With a locked rate, 9am and 3pm show the identical figure, because the rate is bound to the run, not the clock. The conversation never happens.
Auditability and fairness both depend on this one design choice. Book a demo to see locked-rate payroll in Zaffre HRM.