The US car rental service designed for inner-city dwellers is planning a $75 million US stock market float.

Zipcar, which has been battling to achieve stead expansion since its inception a decade ago, hopes to raise $75 in the move, which was announced yesterday after the successful acquisition of the UK franchise Streetcar – which offers similar car-sharing and cost-savings plans. $5 million will be used to payback former Streetcar investors.

Zipcar can claim to be the pioneer of the US car sharing program, which sees members provided with daily or even hourly rates as part of the membership benefits. The program has proven successful, particularly in areas where there are low levels of car ownership or where parking facilities are either expensive or non-existent such as college campuses and urban concentrations. So popular has the scheme proved that rival car rental companies Enterprise and Hertz have also launched their own variations.

In April, Zipcar took over Streetcar in a deal estimated to be worth around $50 million, which was seen as confirmation of Zipcar’s intention to expand into Europe. To date, there are over 400,000 Zipcar members across the US, where it is offered in 13 major cities and over 150 college campuses.

Zipcar has experienced losses for every year since it was founded ten years ago, with regulators also posting a loss forecast for 2010. While the first quarter profits for this year rose by 22.5 per cent to reach $33.2 million, the group’s net loss has risen from $3 million to $5.3 million, not taking into account the Streetcar partnership.