The record betters a fellow Ford small car, the Escort, which got 4,105,961 registrations during its 14-year reign. The Escort was sold in the UK between 1968 and 2000. The Fiesta name has been around for 37 years in the UK, and the car has topped its class for 27 of those.
According to reports, models fitted with the award-winning 1.0-litre EcoBoost engine account for 40 per cent of sales, while 90 per cent of buyers go for higher-spec variants.
The Fiesta has been the top-selling car in the UK for the past four years running.
Locally, the Fiesta doesn't enjoy the same levels of success - to the end of June 2014, the Fiesta sits in sixth place in the city car segment behind the likes of the Hyundai i20, Mazda 2, Kia Rio, Suzuki Swift and Toyota Yaris.