The policy discourse on active ageing and well-being at the European level tends to have a strong focus on the experiences of the 'young old'. In this study the focus instead is on the oldest old (75 years and older). The theoretical framework is inspired by the Active Ageing Index and the Nordic welfare research tradition. Active ageing and well-being indicators and domains of high relevance for the oldest old are used and a new Active Ageing-Well Being Index (AA-WB Index) is developed. Our aim is to go beyond averages and analyse changes over time and inequality in the AA-WB Index. The prime data is derived from two waves, 2004 and 2014, of the Swedish Panel Study of Living Conditions of the Oldest Old (SWEOLD), a nationally representative sample of older people. The results show an overall improvement in most domains of the AA-WB index, especially in the indicator participation in cultural and leisure activities. The findings also show clear and consistent gender and educational inequalities. In addition, the different domains correlate, implying that inequality within a domain is aggravated by the inequality in another domain. The study highlights that measurements on active ageing and well-being should place a greater importance on the living conditions of the oldest old with a special focus on inequality.