Understanding how long information and communications technology (ICT) products are used, when they are disposed of, and underlying drivers for consumer behavior, play a defining role in the potential success of current and future policy strategies on circularity in the electronics sector. In this study, we explored the service life and storage stages of four types of ICT products in Denmark, namely mobile phones, laptops, tablets, and desktop personal computers (PCs), using dynamic material flow analysis (MFA) with sales-stock-lifetime reconciliation capability. Further, we characterized the stock of products in Denmark and its dynamics from 1990 to 2018, and extract evidence on how obsolescence and technological shifts affect product service life. Results showed that the active use stock of analyzed ICT products has either stabilized (mobile phones, laptops, tablets) or is decreasing (feature phones, desktop PCs). The dead storage stock of smartphones, laptops and tablets continues to expand and in 2018 accounted for 30% of their combined total stock. Results highlight that the technological shift from feature phones to smartphones was likely accompanied by a drop in mobile phone service lifetime from 3 years to around 2 years between 2008 and 2012. Furthermore, our results suggest that product physical obsolescence was not the main driver for the length of service life, while intangible product qualities may play a significant role.