Public Transportation from Sao Paulo Guarulhos Airport to your destination, and bus transfer from/to Congonhas Airport :  (Note that most taxi drivers do not speak English.)

Until 2015, there is no direct train service into Sao Paulo, as Jade line 13 to Guarulhos won't be ready until 2015 - meanwhile, a minimum of 2, and most likely 3, transfers on already overcrowded subway trains are needed to get to any of Sao Paulo sites.

By Subway/ Commuter Train  via Bus- 

bus will take you to the following subway stations - the closest of which is Tiete for blue line 1; or to three other stations (all with red line 3) - Barrra Funda, Republica & Tatuape.
(Jade Line 13 of the CPTM Guarulhos commuter train will extend to neighboring city of Guarulhos - completion: 2015).

By Bus:
1. EMTU buses serve  Sao Paulo's Itaai Bibi, Metro Tatuape, Paulista Augusta, Republica (Republic Square), Barra Funda & Terminal Rodoviario Tiete.  EMTU buses also serve as connector to Congonhas Airport.
2. Transurbano Guarulhos (Antigo Guarupas):
Bus 331 to Terminal Cecap
Bus 332 to Rodoviaria
Bus 436 to Jardim Santa Mena
Bus 488 serves the Airport Circle
Bus 723 to Terminal Pimentas via Monteiro Lobato
Bus S132 - Airport /center - via Circuito Gastronomico
Bus 172 for international shopping
3. Capioli bus takes you to Campinas
4. Pasaro Marrom buses take you to: Aparecide, Cachoeira Paulista Cruzeiro; Campos do Jordao, Guarantingueta, Sao Jose dos Campo & Taubate.
5. Litoranea Buses take you to Barra do Una, Bertioga, Boicucanga, Caraguatatuba, Maresisas, Sao Sebastiao, & Ubatuba.
6. Viacao Cometa buses take you to: Santos, Saso Vicente, & Sorocaba.

Shuttle Bus Service from/to Congonhas CGH to/from Guarulhos GRU Airports runs every 30 minutes, costing about R$40. For more information open http://www.airportbusservice.com.br/en/linhas .

By Train - Transportation improvements scheduled for late 2014 -2015 and beyond: 
1. A new  bus terminal - to be completed.
2. Jade Line 13 of the CPTM Guarulhos commuter train will extend to neighboring city of Guarulhos - completion: 2015.
3. Access routes to the Airport will be expanded 'with the arrival of Ring Road & Line 13 Jade CPTM'. 
4. Ongoing work on the new Onyx train line 14 - the 'Airport Express'  (a high-speed train connecting Guarulhos Airport with both Rio de Janeiro and Campinas airports) is intended to  to reduce travel time to the City by 20 mins . No completion date is yet available.)

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