People, and their dependents, who are employed yet are not earning enough to put them above a certain poverty line threshold. In the United States in 2000, 31 million people earned under a specified amount determined on the size of their household (e.g.: $17,603 for a family of four), and of these, 4.7% had spent the last 27 weeks in the labour force.

Single women (5.5%) are more likely to form part of the working poor than single men (4.0%), but married women (1.8%) are more likely to be married to a breadwinner than a married man (3.0%). Disturbingly, 16.7% of working women who maintain a family are poor.

Working Hispanics (10.0%) and blacks (8.7%) are also more likely to be poor than working whites (4.0%). Black mothers maintaining a family are three times more likely to be in poverty than white mothers.

Education qualifications also count - some slackers might be living off waiting tables and belong to the working poor, but their numbers are minute (1.4%). Those whose highest qualifications are an associate degree are slightly worse off (2.5%), but they are still luckier than those whose schooling finished at high school (5.4%), or did't even finish that (12.9%).

31% of the working poor was engaged in the service industry, with 20% of these working as domestic servants.