The founder of Go Compare has reportedly appointed advisers to look at selling the business, putting her in line for a windfall of around £100 million.

Hayley Parsons has hired the accounting firm Grant Thornton to conduct a strategic review of the company, which she launched in 2006. The business is reportedly valued at £500m.

Ms Parsons is thought to be weighing up options ahead of the planned stock-market flotation of the motor insurer Esure, which owns 49% of Go Compare.

The expected flotation of Esure may allow Penta, the Glasgow-based private equity operation, to crystallise a big increase in the valuation of its investment in the insurer.

In February 2010, Penta Capital and a group of institutional investors backed a team led by Peter Wood to complete a management buyout of the company he founded from Lloyds Banking Group. A big employer in Glasgow, Esure was valued at around £265m.

The successful flotation of Direct Line last month appeared to reflect significant appetite among institutions for insurance businesses, in spite of the prospect of big regulatory changes.

Royal Bank of Scotland raised £787m by selling 30% of the shares in Direct Line in an offering that valued the subsidiary at £2.6 billion.

Newport-based Go Compare, fronted by fictitious opera singer Gio Compario, was founded by Ms Parsons in 2006 after she left rival insurer Admiral's Confused.com.

Esure, fronted by Michael Winner in its television adverts, has stated it has "no plans to increase its stake" in Go Compare.

Go Compare provided a quote every second in 2011 after a 15% rise in the average cost of comprehensive car insurance to £971.

Profits at the website, which also provides pet, travel and life insurance, rose 15% to £34.7m, while turnover increased 7% to £108.9m. This reportedly saw Ms Parsons pick up £3.2m in dividends.

Ms Parsons holds a 23% stake in the company valued above £100m. The rest is held by staff and other shareholders. Go Compare and Grant Thornton were not available for comment.