'To explore how an informal job in formal employment can be define and who has an informal job and what the labour market outcomes are, are the research objectives, this paper uses data of comparable face-to-face surveys in nine countries: Benin, Ghana, Guinea, Kenya, Madagascar, Niger, Rwanda, Senegal, and Togo. An index for job-based informality is developed, based on contribution and entitlement to social security and employment status. In all countries, the young and low-educated workers are more likely to hold informal jobs: even more so are workers in micro-enterprises and private industry, and to a lesser extent those in unskilled occupations. Women and men are equally likely to hold informal jobs in formal employment. The more informal, the poorer the labour market outcomes: wages are lower: the chances of being paid below the minimum wage, working more than 48 hours, and not being covered by a collective agreement are higher.'