Existing home sales fell 0.2% in March, to an annualized pace of 4.59 million units.
Economists polled by Bloomberg were looking for a decline to 4.56 million units.
The pace of sales is the slowest since July 2012.
This compares with a 0.4% decline to an annualized pace of 4.60 million units the previous month.
Pending home sales, considered a leading indicator for future existing home sales, unexpectedly fell in February and have been trending down for some time.
“With mortgage applications looking more or less level in recent months – accounting for the usual Feb/Mar seasonal adjustment chaos – we are hopeful that any further decline in sales in Q2 will be marginal,” said Ian Shepherdson at Pantheon Macroeconomics.
“Though we continue to worry that the market is very vulnerable in H2 if the broader economy picks up and drives Treasury yields higher, as we expect.”