Quick question. Tax code was wrong from 2003/2004. Dh called HMRC in November and they said he could claim back as far 2005-2006. He sent all details to them. Heard nothing for ages. He called (£25 worth of calls) only to be told "they never got letter". Dh sent it again in April. Just received letter stating. When you rang November 2011, you could still claim back to 2005-6 but the 2005-6, 2007-7 and 2007-8 tax years have since gone out of date! That means approx £4k lost. Where do we stand as dh did contact them and write in time. Then as soon as finding out they'd not got it, he sent them again. And how on earth does 3 tax years get wiped in 5 months? Anyone with expertise?