Strong fleet and commercial sales have given another boost to the surging Scottish car market, with a sharp increase in registrations last month.

Figures released by the Society of Motor Manufacturers and Traders (SMMT) have shown new car purchases for September 2013 up almost 14% when compared to the same period last year.

In total, last month saw 41,367 new registrations, eclipsing the September 2012 tally of 36,333.

The overall number of new car sales in Scotland for 2013 now stands at 165,134, which represents an increase of 13.4% when compared to the total from January to September, 2012.

Douglas Robertson, chief executive of the Scottish Motor Trade Association (SMTA), attributed the swell in sales to the commercial sector, where new registrations were more prominent.

He said: "We are delighted with these figures and it shows a significant increase in business and fleet sales during the month of September which has contributed to the increase.

"This is good news for the retail motor trade and SMTA member dealers in Scotland. We are optimistic that we will exceed recent revised expectations by the end of the year of 190,000 units."

The Vauxhall Corsa remains the most popular new car in the country with 2997 new registrations last month alone. It remains at the top of annual figures with 9207 sales so far this year.

The Ford Fiesta is the second most common model, ahead of the Ford Focus and Vauxhall Astra.

The picture in Scotland is similar to that across the United Kingdom, which showed an average increase of 12.1%. Indeed, for the UK as a whole, September 2013 is best performing month since March 2008.

SMMT chief executive Mike Hawes said: "Robust private demand has played a major role in this growth, with customers attracted by exciting, increasingly fuel-efficient new models offering savings in the cost of ownership.

"With fleet and business demand still to reach pre-recession levels, we believe the performance to be sustainable. The latest 63-plate should deliver success into next year."

One of the most notable explanations for the steady increase in sales is the wealth of new car incentives laid out by manufacturers.

Herald motoring correspondent Stephen Park, secretary for the Association of Scottish Motoring Writers, suggests the lure of personal contract purchase (PCP) deals has helped to restore public faith in the industry.

He said: "PCP deals have been one of the main drivers behind the increase in new car sales. Essentially, these incentives mean that most people can drive away with a brand new car for as little as £100 per month.

"Deposits are much lower and newer cars have greater fuel efficiencies, meaning the cost of driving can be reduced by purchasing a new model. Also, the sheer range of new models available has never been greater."

He added: "September has always been a good barometer for how the industry is performing.

"Sales throughout 2013 have been rising steadily against 2012, which shows consumer confidence is returning and people are now more willing to buy."