A fall to 405,000 had been forecast. However, the number rose by 2,000 to 414,000 last week, stirring fears of labour market stagnation.
The figures from the Labor Department said the number of new benefit claimants had suffered no discernible impact from the severe storms battering the country.
Excluding one week in early August, new claims have held above 400,000 since early April.
Total insured unemployment for the week ending 27 August, however, fell to 3,717,000, according to initial estimates – down 30,000 on the previous week’s revised figures of 3,1747,000.
The overall number of claimants across all programmes was also down to 7,169,176, meaning the figures fell by 167,009 from the previous week.