The German brand has been described as ‘benchmark’ of the compact class.
It is a fourth-generation and an aggressive facelift with a lowered front end, new grille, longer and wider wheelbase, and larger wheel arches for a more spacious feel.
It has intelligent voice control features for the first time in a Mercedes-Benz and can be activated using the phrase: ‘Hey, Mercedes.’
This can control destination input, phone calls, music selection, messaging, weather forecasting and climate control.
The dashboard has been replaced by two ‘floating’ screens – as seen in other Mercedes models. Customers can select either two seven-inch displays, two 10.25-inch screens or one of each.
Under the bonnet the A-Class is available with either a 1.4- or 2.0-litre four-cylinder petrol engine, with 161bhp and 221bhp respectively, or 1.5-litre (114bhp) diesel engine.
Meanwhile, new MacPherson front and multi-link rear suspension should lead to a better ride and improved handling.
Ambient lighting with 64 colours, illuminated air vents in a turbine look, heated seats, climate control and massaging seats are also optional extras.
An array of new safety tech includes Distronic distance control, active steering assist, emergency stop assist, active lane change and a semi-autonomous driving mode.
However, the A-Class still retains its practical nature.
The longer and wider body gives occupants more shoulder, head and leg room as well as increased space for luggage.
A Night exterior package is also available, with 18-inch alloys, black mirror housing, a diamond grille, and tinted windows.
Gorden Wagener, chief design officer, said: “The new A-Class embodies the next stage in our design philosophy of ‘sensual purity’ and has the potential to usher in a new design era.
“With clear contours and sensual surfaces, we present high-tech that awakens emotions.
“Form and body are what remain when creases and lines are reduced to the extreme.
“The interior represents modern luxury at a level previously unattained in this class, and translates intelligent technology into an emotional overall experience.”
Mercedes has yet to release prices for the car, but the current generation starts at £20,715.