Anyone who reaches State Pension age on or after 6 April 2016 will fall under the new rules for State Retirement Pensions. People who reach State Pension age before this date will get their State Pension based on the current rules.
You can claim your State Pension when you reach State Pension age. State Pension age is different for men and women (but this is gradually changing) and depends on your date of birth. You can check when you will reach State Pension age on the gov.uk website.
The new rules will affect men born on or after 6 April 1951 and women born on or after 6 April 1953. If you will reach State Pension age before 6 April 2016, your State Pension will be calculated based on the current (old) rules. If you are already receiving your State Pension, you will not be affected by these