HIV testing and antiretroviral therapy (ART) has scaled up tremendously in Malawi in the last 5 years. We analyzed trends of HIV testing uptake in the course of ART scale-up in 25 government and mission hospitals, which were selected because they do not receive support from non-governmental organizations. Data on numbers of clients HIV tested and on cumulative ART registrations were collected from annual country-wide situational analyses and from quarterly ART supervisory visits from 2002 to 2007. In the period before ART scale up, the quarterly number of clients HIV tested increased from 2609 in 2002 to 8197 in 2004, equivalent to an average quarterly increase of 559 tests. During ART scale up, the quarterly number of clients HIV tested increased from 17977 in early 2005 to 35344 in the second quarter of 2007, equivalent to an average quarterly increase of 2171 tests. During this time, the cumulative number of patients started on ART increased from 2441 to 29756. There has been a rapid acceleration of HIV testing uptake and ART in government and mission hospitals. ART may facilitate the decision of clients to have an HIV test and therefore contribute in this way to HIV prevention efforts.