But that date is a fiction for most people as payment of the state pension normally begins not on the day you reach your pension age but on the next 'payday', which can be up to six days later.
Women born between November 6, 1951 and December 5, 1951 reached state pension age on Saturday, July 6, 2013, for example. But in fact it might not have started until Friday, July 12, because the state pension begins on a 'payday' - always a weekday - and the day depends on the last two digits of your National Insurance number.
Are you one of the women disadvantaged by the changes to state pension age?
The only people who get their state pension from day one are those whose retirement age and birthday fall on the same day of the week. The rest have to wait up to six days.
Even the name 'payday' is misleading, as the state pension is now routinely paid four-weekly in arrears. So these women would not have been paid until August 5. You can ask for it to be paid weekly in arrears.
Could you boost your income by deferring your state pension?
The rules for people who reached pension age before April 6, 2010 are different - their 'payday' is normally a Monday or a Thursday and they can apply to have it paid weeky in advance.
Check your pension 'payday' against your National Insurance number:
Last two digits of NI number ('Payday' state pension begins): 00-19 (Monday); 20-39 (Tuesday); 40-59 (Wednesday); 60-79 (Thursday); 80-99(Friday).
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