Podczas londyńskiego Motor Show zaprezentowano Vanguarda z poprawionym wlotem powietrza, większą szybą tylną i pokrywami na tylnych kołach. (Phase IA)
Standard Vanguard I models (first introduced in 1948; modified versions for 1950 easily distinguishable by full spats over the rear wheels) are continue into 1951 with no modifications of note. Available are a four-door Saloon and Estate Car, both fitted with a four-cylinder, 2088-cc power unit which develop 68 bhp at 4200 rpm. Laycock-de-Normanville overdrive became optionally available in the summer of 1950; the Vanguard is one of the first British cars to offer this facility. Prices are £726 for the Saloon and £877 for the Estate Car.
Standard Vanguard (Series 20S) Saloon was given an external face-lift for 1952 with the adoption of a slightly lower bonnet line, a wide almost rectangular chrome-plated air-intake with a central horizontal bar, a wider rear window and push button door handles. Those changes were introduced at Earls Court.
Vanguard z rolowanym dachem Tickforda.