CERTIFICATES NATIONAL SAVINGS INTEREST FREE OF INCOME TAX Each Savings Certificate costs 15'- and grows each year in value. In 5 years' time it is worth 17'6: in 10 years 20'6. You can cash them at any time. The maximum holding for any individual is 500 Certificates costing £375. Savings Certificates can be bought at any Post Office, Bank, or Trustee Savings Bank; through a Savings Group, or from Shops acting as Honorary Official Agents. You can buy Savings Certificates by instalments; 6d. National Savings Stamps are on sale and a stamp book in which to collect them is supplied free.