by business editor Trevor Sturgess

Affinity accounts are to be offered to Charlton Athletic Football Club fans after Kent Reliance Building Society agreed a six-figure shirt sponsorship deal.

The Chatham-based society added the Addicks to the Gills in its portfolio of sponsorships and said supporters would be offered products, including affinity accounts, that will be "mutually beneficial to the club, supporters and the Society."

The Charlton deal, thought to be in the region of £100,000, is a good one, giving them promotional opportunities across a swathe of the Thames Gateway regeneration area, south east London and the rest of Kent.

With the Addicks relegated last season to League 1, the cost of shirt sponsorship fell steeply and meant the society snapped up the deal for what, in football terms, was a song.

When Charlton was in the Premiership, Spanish property firm Llanera pumped £6.6m into the club in a sponsorship package that included a shirt deal.

That deal was celebrated by events at The Valley and in the House of Commons, while the latest agreement was sealed in a far more low key.

Rob Procter, deputy chief executive, said: "The rationale for the sponsorship is that Charlton has 17,000 season ticket holders, two thirds of the fans are from Kent. They have a very big fan base in Kent and a strong community base, so their objectives marry very well with ours. It’s a fantastic deal."

While the deal represents the going rate for a demoted team, it is likely to rise with promotion. Mr Procter added: "We don’t see it as being in competition with Gillingham, we see it as complementing the sponsorship we’ve got with the Gills."