De facto marital status (that is, including cohabitation) was ascertained by combining the information on marital status with whether the respondent was currently cohabiting. Cohabiting couples were defined as people who were living together in a household as a couple without being married to each other. Respondents who were single, widowed, divorced or separated but who were cohabiting are here classified as cohabiting - rather than by their legal marital status - while those not cohabiting are classified by their marital status.

In 2001, the de facto marital status of adults aged 16 and over was as follows:

• 54% of men and 52% of women were married;
• 10% of men and 9% of women were cohabiting;
• 27% of men and 18% of women were single;
• 3% of men and 11% of women were widowed;
• 6% of men were either divorced or separated, compared with 9% of women.

Among the total adult population in 2001 over twice as many women as men were either married or cohabiting in the 16 to 24 age group; 7% of women were married compared with 3% of men, and 17% women were cohabiting compared with 8% of men. This difference decreased among those aged 25 to 34 with 70% of women married or cohabiting compared with 58% of men. Among people aged 35 to 44 there was no difference between the proportion of men and women who were married or cohabiting (76%).