Millions to get tax demands and rebates in the post
16 May 2012 Last updated at 15:56 BST
This week around one and half million people will get an unexpected tax demand through the post.
That is on top of the three and half million people who get tax rebates that are part of annual reconciliation of paid tax, which sorts out the difference between tax collected and tax owed.
BBC Radio 5 live Wake Up To Money asked George Bull, a senior tax partner at accountants Baker Tilly, what to expect.
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