The brand, owned by Mondelez, has set up meetings with around six to eight creative agencies to see at chemistry stage.
It is planning to draw up a shortlist of agencies to see at pitch stage. The process is being run direct.
A Mondelez International spokesperson said: "As common with all businesses we regularly talk with different creative agencies as well as those we currently work with. We are too early in the process to share any further information on the creative work for our Philadelphia brand."
The incumbent is J Walter Thompson, who won the £35m pan-European creative account in March 2015 without a pitch. The agency has a long-standing relationship with Mondelez and had worked with the brand for decades until 2013, when Bartle Bogle Hegarty won the account following a pitch.
But BBH and Philadelphia only worked together for a year, producing one campaign. In September 2014, the business was initially moved in-house, before being handed back to JWT six months later.
In February, The Sunday Times reported Mondelez was looking to sell off its newly created cheese and grocery division, including Philadelphia – the division’s largest brand.
Mondelez said: "We don't comment on market rumours. What I can confirm on our cheese and grocery activity is that we see it as a good business, with solid margins and cash flow, which helps to provide scale in some markets. The team is executing well, having posted solid growth for 2015."