In 2011, Singh worked as Director of Digital for the No To AV referendum campaign. Singh co-founded WESS Digital with Matthew Elliott, Paul Staines, and Andrew Whitehurst in 2013. The firm created a database based on issue-based campaigns to be used by political parties to analyse how people vote.
He was listed in Iain Dale and The Daily Telegraph's list of top 100 left wingers in 2008. In 2018, Singh was in the Financial Times list of the UK's top 100 black and minority ethnic leaders in technology.
- "The UK's top 100 black and minority ethnic leaders in technology". Financial Times. Retrieved 26 November 2018.
- "'We own the political market', says MessageSpace co-founder Jag Singh". Campaign Live. 26 July 2016.
- "Guido Fawkes editor in big data analysis venture". Research Live. 15 March 2013.
- "New Statesman co-owner buys LabourHome blog". The Guardian. 24 July 2008.
- Singh, Jag (16 May 2011). "Jag Singh: Labour's digital expert on the No to AV campaign". PR Week.
- "Campaigners target political parties with ambitious plans". PR Week. 14 March 2013.
- "Top 100 left wingers: 100-76". The Telegraph. 19 September 2008.