This paper presents data from a cross-sectional survey of 3014 adult carers, examining use of the Internet and factors associated with it. Carers recruited from the databases of three local authorities and other carer organisations within their geographical boundaries and that of Carers UK, a national carers organisation, were sent a postal questionnaire (response rate: 40%). A comparison of our data with national data on carers suggests some under-representation of men and younger adult carers and some over-representation of those who had been caring for long periods and those with substantial caring responsibilities. Two measures of Internet use were used and are presented in this analysis: previous use (ever used vs never previously used) and frequency (less than once a week vs once a week or more). Bivariate analyses identified patterns of Internet use and socio-demographic and socio-economic factors and caring circumstances associated with them. Factors significantly associated with each measure of Internet use were entered into direct logistic regression analyses to identify factors significantly associated with each measure. Half (50%) of all carers had previously used the Internet. Of this group, 61% had used it once a week or more frequently. Factors significantly associated with having previously used the Internet were carer's age, employment status, housing tenure and number of hours per week they spent caring. Frequency of Internet use was significantly associated with carer's age, sex, employment status and number of hours spent caring. Our study suggests that a significant number of carers may not currently be Internet users and that age, gender, socio-economic status and caring responsibilities shape Internet use in particular ways. Given the targets set by government for the development of online services, it is important to address the digital divide among carers and to continue to develop other services and information systems to meet the needs of those who do not access the Internet.