Apart from the regular rag-top version for the Astra, GM considered that a retractable hard-top version would boost the image and the sales for its compact-segment U.K. representative.

When GM started to develop the coupe-cabriolet version for the Astra, there was no financial crisis in sight. Not even when the car was introduced on the market there were no signs of financial troubles. Yet, they came and the European arm of the GM was on the brink of extinction. It dodged the bullet and a few special cars remained in production, such as the Astra Twin-Top.

The Astra TT kept the same front fascia from the Astra J generation. The raked A-pillars were similar to those on the GTC version but thicker since they were used as a roll-over protection system. To make the car safer, the Astra TT was reinforced and achieved a 30% higher rigidity than a standard convertible. At the back, the trunk was easy to access due to an intelligent system that allowed the roof to be raised and allow storage.

Inside, there was room for four adult passengers, but with limited legroom for the rear ones. The front seats were carried-over from the GTC model.

Under the hood, the Astra TT took only a few engines from the Astra line-up, but fortunately, it took the more powerful ones. The base version was the 115 hp naturally aspirated unit, while the top version offered 200 hp. A diesel version was available as well.