Britain’s biggest building society has used Havas Media as its planning and buying agency since 2008.
Industry sources said Sara Bennison, chief marketing officer at Nationwide, has been keen to review its media arrangements since she started earlier this year.
It is thought the brand is planning chemistry meetings with agencies from holding companies including WPP, Omnicom and Publicis Groupe, as well as the incumbent, Havas.
Nationwide confirmed the review but would not comment on any approach it has made to agencies.
Bennison was chief marketing officer at Barclays when it appointed Maxus to handle media. The WPP shop is unlikely to pitch for Nationwide because of the Barclays conflict.
Nationwide appointed VCCP as its creative agency last year after an acrimonious split with 18 Feet & Rising.
Joe Garner, who joined Nationwide as chief executive last month, used to lead BT’s Openreach arm. Nationwide has said it wants to make "further investment in our brand to broaden our appeal and support business growth". Profits rose to £1bn last year.