Index-linked Savings Certificates

Index-linked Savings Certificates are British inflation linked bonds from National Savings and Investments, the state-owned savings bank in the United Kingdom. The bond terms are typically 2, 3 or 5 years. The returns are linked to Retail Price Index with a tiny added interest rate on top. The Bonds can now only be cashed in at maturity.
Index-linked Savings Certificates are free from UK income tax making them relatively attractive to tax-payers, particularly higher rate tax-payers. They are backed by the Treasury of the UK Government so are considered to be safe deposits. The certificates used to be informally known as "Granny Bonds" because they were originally only available to savers who were over the retirement age. This is no longer the case.

Issues

The bonds come in issues. Each issue has a per person investment limit, which as of 2011 was £15,000.
On 19 July 2010, due to high investment levels the certificates were withdrawn from general sale in order to keep investments within the financing target set by HM Treasury. After re-introduction in May 2011, this happened again on 7 September 2011.