Savers who purchased generous government bonds exclusively available to those aged 65-plus at the start of the year will face a difficult decision in January as the one-year 'pensioner bonds' mature.The bonds, unveiled by chancellor George Osborne in his 2014 Budget, offered a fixed savings rate of 2.8 per cent over one year and 4 per cent over three.Come January, people who bought the one-year bonds will be getting their money back plus interest.Some estimates put the number of savers who snapped up the one-year bonds during their brief sale period in early 2015 at over a million. Savers who put the maximum allowed £10,000 into the one-year bonds will have earned £280 in interest before tax.Challenger banks on topBut savers will be hard-pressed to find a home for their money that is as secure as the NS&I bonds while paying a comparable rate.According to financial comparison website Moneyfacts.co.uk, savers will have to turn to relatively newly launched challenger banks to find rates on one-year savings bonds anywhere near those previously offered by the NS&I pensioner bonds.As of 7 December 2015, Shawbrook Bank offered the best one-year rate of 2.15 per cent, with FirstSave coming second at 2.12 per cent.High Street banks offer comparatively meagre rates, with Nationwide Building Society offering 1.5 per cent and Clydesdale and Yorkshire bank offering 1.4 per cent. Metro Bank also offers 1.4 per cent, and sits somewhere between a challenger bank and an established high street name.'Savers will no doubt remember the struggle to get their hands on one of the lucrative pensioner bonds at the start of ,' says Rachel Springall, finance expert at Moneyfacts.'The rates offered stood head and shoulders above those paid by other providers, so NS&I were bombarded by millions of eager savers looking to secure a good home for their money. Sadly, these customers will now have to battle to find decent returns elsewhere when their bond expires.'She adds that once savers have chosen their money's next home, they need to inform NS&I well in advance, either by post or online. Telephone instructions will not be considered.