OMD, which tendered through its OMD Connect brand on a direct response platform, has been knocked out of the pitch.
Both MPG and PHD are awaiting a final decision, which is expected imminently.
AAR is handling the review, which covers both media planning and buying and is worth about £12m annually.
MPG has held the account since ING Direct, the internet banking division of Dutch banking group ING, launched in the UK three years ago.