It may come as a surprise to many Twitter users, both young and old, to find out that there are many cardinals who are very active on Twitter, this is a non-exhaustive list as I am sure more cardinals will become active on Twitter in the coming weeks, months and years. As such if I have in fact missed any of the cardinals off of this list, please let me know in the comments below and I will rectify it.
On the contrary, this list has been extensively researched and compiled to ensure that this list is completely up to date as of October 2015 and will continue to be checked on a monthly basis and updated accordingly. The entire list of the College of Cardinals which is maintained by Father James Bradley can be seen here. This is an unofficial list but is absolutely up-to-date and correct.
Italy
Cardinal Gianfranco Ravasi: @CardRavasi (Italian) / @CardRavasi_en (English)
Cardinal Angelo Scola: @angeloscola
Cardinal Bagnasco: @conBagnasco (Unofficial account)
Cardinal R. Sarah: @Card_R_Sarah
Cardinal J.L. Tauran: @CardTauran
Giuseppe Betori: @giuseppebetori
Austria
Christoph Schönborn: @KardinalWien
The Netherlands
Cardinal Eijk: @Eijk
Czech Republic
Cardinal Dominik Jaroslav Duka: @dominikduka
France
Cardinal Philippe Barbarin: @CardBarbarin (French)
Cardinal Vingt-Trois: @avingttrois (French)
Jean-Pierre Ricard: @CardRicard (French)
Argentina
Leonardo Sandri: @CardinalSandri
Spain
Cardinal Lluis Martinez Sistach: @sistachcardenal
Cardinal José Luis Lacunza Maestrojuán: @CardenalLacunza
England
Cardinal Nichols: @CardinalNichols
United States
Cardinal Timothy M. Dolan: @CardinalDolan
Cardinal Sean P. O’Malley: @CardinalSean
Cardinal Donald Wuerl: @Cardinal_Wuerl
Cardinal Roger M. Mahony: @CardinalMahony
Cardinal Justin Francis Rigali: @CardinalJRigali
Canada
Cardinal Lacroix: @gclacroix
Mexico
Cardinal Francisco Robles Ortega: @cardenalrobles
Cardinal Alberto Suárez Inda: @cardenalsuarez
Australia
Cardinal George Pell: @CardinalPell
Peru
Arzobispado de Lima: @arzlima
Uruguay
Cardinal Daniel Sturla: @DanielSturla
Venezuela
Cardinal Jorge Urosa Sabino: @UrosaSabino
Brasil
Cardinal Odilo Scherer: @DomOdiloScherer
Cardinal Joao Braz de Aviz: @JoaoBrazdeAviz
Orani João Tempesta: @domoranijoao
Colombia
Cardinal Ruben Salazar Gomez: @cardenalruben
Philippines
Cardinal Chito Tagle: @CardinalChito
Dominican Republic
Cardinal Nicolas de Jesus Lopez Rodriguez: @CardenalLopez
Ghana
Cardinal Peter Turkson: @CardinalTurkson
South Africa
Cardinal Wilfrid Napier of Durban: @CardinalNapier
Once again if I have missed anybody off of this list or any of the information is incorrect please let me know in the comment section below. If you would like to see an active Twitter list of cardinals who are active on Twitter, click here.