The two cars achieved three stars for child occupant protection in the #SaferCarsForIndia crash test, Global NCAP said in a statement.
Vehicle safety group said it tested Tigor model as Tiago and Tigor are the same car in the front and passenger compartment.
Tigor/Tiago offers two frontal airbags as standard. Its structure and footwell area have been rated as unstable. Head and neck protection for adult occupants was good, it added.
"Chest protection for passenger was adequate and marginal for the driver. Femur and knees showed marginal protection as there is risk of contracting dangerous structures behind the fascia," it said.
In terms of child occupant protection, the car scored three stars. The Tigor/Tiago does not offer three point belt in all seating positions and does not offer ISOFIX anchorages, it said.
This result follows the recent five star achievement of the Tata Altroz and the previous five star result for the Tata Nexon, it added.
Global NCAP had launched #SaferCarsForIndia Campaign in 2014 with an aim of promoting safer vehicles in the country.
"Between 2014 and 2020 Global NCAP has completed more than thirty-seven safety assessments which have acted as an important catalyst in the safety improvement of Indian cars," it said. RKL BAL