The information, which was stored on a back-up data tape, went missing last August. Zurich has now asked KPMG, a UK-based company that carries out auditing and financial services, to look in to the situation.
The data tape is also thought to hold the details of 550,000 customers who live in South Africa and a further 40,000 based in Botswana.
The information was lost in 2008 while it was being sent between Zurich and South Africa. The data loss has only recently come to light.
The insurance company will be writing to its customers based in the United Kingdom to advise them of the loss and to offer advice to customers to further secure their identities.
Zurich have said that there isn't any evidence that data has fallen in to the wrong hands.
The insurance company has moved to further improve the security of its data and will also take extra measures to ensure the safety of data while it is being transported.
Customers with a UK Life Policy remain unaffected by the data loss.
In a statement on the Zurich
website, Annette Court, who is CEO Europe General Insurance of Zurich Financial Services Group, said, "At this time, our first and foremost concern is our customers and we are doing all we can to support and assist them in these circumstances and have put in place a dedicated response team to help support them.”
“We are implementing the necessary steps to minimise the impact of this situation on our customers. Protecting our customers’ interest is at the top of our agenda. We are putting a great deal of investment into strengthening our internal processes to ensure that incidents of this nature do not happen again in the future.”