The Rocket Man legend is performing part of his Red Piano tour at the concert in the capital and the event's bosses expected huge demand for the show - which will be broadcast on TV networks worldwide.
John will be joined by singer Will Young and recently crowned X Factor champion Alexandra Burke to ring in 2009.
But despite a huge publicity campaign for the show - which has room for 17,000 guests - tickets have failed to sell out in time for 31 December (08).
And in a desperate bid to flog seats, organisers at the O2 Arena are offering a four-for-three deal for paying customers, leaving the entry price for the gig $111 (GBP74) per person - reduced from $165 (GBP110).
Source: WENN