Trade body the Society of Motors Manufacturers and Traders (SMMT) said 109,000 cars were completed in August, nine per cent higher than in 2015 and the highest figure for the month in 14 years.
Sales to the UK grew by six per cent, with exports - which accounts for three-quarters of the industry - growing by 10 per cent in another strong month for the industry.
Read more: UK exports cars to more than 100 countries
The figures will fuel the argument that the depreciation in the value of sterling following the EU referendum is helping to make UK exports more competitive and support the economy in the wake of the shock Brexit vote. On a trade-weighted basis, sterling has lost 15 per cent since its peak in November 2015.
Before the referendum, however, car makers supported a vote to stay inside the EU for fears foreign-owned plants may move elsewhere in order to protect their access to the Single Market.
Despite the speculation, the SMMT indicated it was too early to define how the EU vote was affecting the industry. Mike Hawes, chief executive said the bumper month was due to "multi-billion pound investments made in UK plants over the past few years".
Hawes also said the industry's future depended on "the UK maintaining internationally competitive business and trading conditions".