A quarter of US dollar offshore savings accounts were paying no interest at all on deposits during 28 November to 27 February, according to Investec Bank (Channel Islands).
Additionally, Investec's quarterly US Dollar Offshore Savings Index found a third of accounts were paying less than 0.1% during this period.
As the Fed rate during the time fell from 1% to just 0.25%, the average interest paid on US dollar savings accounts fell by 0.75% to 0.53%.
Although some accounts offered non-existent returns, the Index also found 36% of accounts were paying 0.5% or above.
"While the Fed rate remains so low, it is more vital than ever that savers keep a close eye on the rate of interest they're receiving," says Laura Preston of Investec, Guernsey.
"There are still some competitive rates out there, but it is likely that they will need to be actively sought out."
The US dollar Investec Horizon Account currently offers 1.6% gross, 1.35% above the Fed rate of 0.25%. Available in US dollars, euro or sterling, savers must have $50,000, €50,000 or £25,000 or above.
Advisers can visit: www.investec-ci.com or call: +44 1481 723 506 for more information.
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