Royal Mail is on course to join London's leading stock market index at this week's FTSE reshuffle after a controversial privatisation that has seen its shares soar by 80%.
The group is favourite to enter the premier share league after Wednesday's review by the FTSE Group, which will mean chief executive Moya Greene becomes part of a shrinking elite of women heading blue chip companies.
Ms Greene will be one of just four, along with Burberry's Angela Ahrendts, easyJet's Carolyn McCall and Alison Cooper at Imperial Tobacco - although Ms Ahrendts is set to leave by the middle of next year to join Apple.
Royal Mail's shares have surged since its flotation in October.
Initially priced at 330p, the stock closed on Friday at 594.5p, valuing the group at nearly £6 billion.
Its entrance in the FTSE 100 Index is likely to fuel accusations that Business Secretary Vince Cable sold the group off on the cheap.
This quarter's FTSE reshuffle is set to be dominated by recent flotations, with Alton Towers and Madame Tussauds owner Merlin Entertainments and estate agency Foxtons also on the line-up.
In a sign of strong investor demand for initial public offerings (IPOs), Foxtons was also directly eligible to join the FTSE 250 after its impressive stock market debut in September.
A recovering housing market has helped Foxtons bank a surge in value, up from £649 million at the start of trading to £829 million at the end of last week.
The UK's improving economic prospects have played a part in boosting investor confidence and appetite for shares in recent floats - fuelling a flurry of companies to seek stock market listings.
Based on Tuesday's closing prices, the results of the FTSE Group review will be announced after market close on Wednesday.