Internal problems with national insurance numbers were caused by
errors in Whitehall systems rather than taxpayers using the wrong
numbers.
Following revelations in last week's Computer Weekly that taxpayers
were told they had been using the wrong national insurance numbers,
the Inland Revenue claimed this was a result of "routine" data
cleansing rather than any problem with the systems.
But now an internal Revenue journal, Insight, has revealed that the
Revenue was due to bring down parts of the main departmental PAYE
systems for two weeks to "remove duplicated national insurance
numbers and put right errors" in advance of the introduction of new
tax credits.
"[With new tax credits being introduced] it is vital that Revenue
systems have the right customer details held under the right
national insurance number," the journal said.
The problems with national insurance numbers were first highlighted
on BBC Radio Four's Moneybox programme, after it was contacted by
IT specialist Sarah Wilkinson. She said she had been using the same
national insurance number all her working life but was being told
by the Revenue to use a new "correct" number.
The letter was one of hundreds of thousands sent out by the Revenue
after an internal data cleansing exercise. When several records for
an individual were found under different national insurance
numbers, a new computer system, codenamed CR74, recommended a
single number to use in future.
Wilkinson said this week, "The implication in the letter is that I
am responsible, but it now seems that the problem is widespread,
which is even more worrying. My concern now is that for the last 20
or so years I have been paying contributions to a national
insurance number possibly shared by someone else. I am not sure
that I trust the Inland Revenue to sort this out."
An Inland Revenue spokeswoman said the problems would be corrected.
Anyone who is worried should contact their tax office, she added.