The centres - in Atherstone, Warwickshire; Bathgate, West Lothian; Cardiff; Skelmersdale, Lancashire; Wakefield, West Yorkshire; and Greenford, west London - will be staffed by 2,700 temporary seasonal workers.
They will open from mid-November and will help deal with the tens of millions of parcels sent during the festive period.
Royal Mail handled almost 150 million parcels last Christmas.
New Christmas jobs
There is currently no detail about exactly how the jobs will divide between each centre.
With six centres, if jobs were divided evenly between each one, then there would be 450 jobs per centre, but Royal Mail has yet to issue further details on each Christmas post hub or on how to apply.