The foreign exchange swaps and forwards market is heading into uncharted waters. From the start of next year, the biggest dealers will adopt a new way of measuring counterparty credit risk capital. The new method will hike costs for some trades. For others, costs may fall.

Gauging the overall impact on a single portfolio, let alone an entire bank, is tricky. But most dealers expect capital requirements to increase and, as a result, spreads to widen.

“There will be a segment of liquidity