Regional units found further support as the Chinese yuan headed towards its biggest one-day gain in four weeks on corporate demand.
But trading was subdued overall with financial markets in Japan, South Korea and Thailand closed.
The ringgit rose as much as 0.5 percent to 3.2500 per dollar, its strongest since April 22, on demand from offshore funds and on lower bond yields.
The Singapore dollar gained as a break of 1.2500 to the US dollar caused investors to cover short positions.
The Taiwan dollar firmed on foreign financial inflows.
Indonesia's rupiah tracked gains in regional peers.
The rupiah fell earlier in the day as data showed Indonesia's economy grew at its slowest pace in more than four years in the first quarter.
A ban on mineral exports and aggressive interest rate rises aimed at reining in a large current-account gap sapped some of its momentum.