The decision means that either MediaCom or ZenithOptimedia will take the brief, which includes the media planning and buying accounts for Prudential, Egg and M&G Investments.
Industry sources suggest that MediaCom is now in the strongest position to take the brief, which is due to be combined into a single agency.
The cutting of the shortlist means that Omnicom agency PHD loses its grip on the £8m media account for the Prudential business. MediaCom and ZenithOptimedia Group agency Zed Media are also incumbents on the business, with MediaCom handling the £12m Egg business and Zed handling the planning and buying for M&G Investments.
The decision to award the account rests with Alison Wright, who was promoted from chief marketing officer at Prudential-owned finance company Egg to oversee the Prudential group's marketing activity.
Wright is a former managing director of Manning Gottlieb OMD. She took over the reins at Egg in January, moving from creative agency WCRS, where she oversaw the Abbey account.
Starcom and Carat, which were part of the original shortlist, were cut from the pitch in May this year.
Last December, Prudential bought the final 21.7% stake in Egg it had not previously owned. The buyout followed an unsuccessful attempt to sell its interest in Egg.
Prudential refused to confirm the reduction in the shortlist competing for the media account.
If you have an opinion on this or any other issue raised on Brand Republic, join the debate in the .