The rule for correct usage of less and fewer is simple: less applies to singular nouns (including mass nouns), and fewer applies to plural nouns. These writers use less and fewer incorrectly:
Although it is a maximum-security facility, less than 144 minimum-security male inmates are kept there . . .
Less players, less schools giving out scholarships. [Lax Magazine]
ten items or less
Less people working means less need for work uniforms . . . [Investor Place]
(In this last example, the second less is used correctly.)
There are exceptions. In measurements of non-discrete quantities such as time, space, or money, less is correct:
With less than 45 seconds on the clock . . . [Glasgow Daily Times]
A one-way fare costs less than $50 . . . [Whig]
Low voltage electricity (less than 500 volts) does not normally cause significant injury to humans. [Journal Gazette]
In past years, that figure would have been less than 20 percent, he said. [Chicago Sun-Times]
One less
Because fewer only applies to plural nouns, one less is correct (even if it sounds funny to strict grammarians):
If they held one less seat, there would be no choice but to win over a Republican . . . [NY Times]
And this is incorrect usage:
That leaves him with one fewer social connection, and that much closer to himself lapsing into loneliness. [Boston Globe]
