Millions of people may be planning retirement on wrong information after "bungling" by the Government, MPs have warned.
The cross-party Work and Pensions Committee said details sent out about when individuals will get state pensions and how much they are worth were "inadequate" and "confusing".
Women are particularly vulnerable to problems as their retirement ages are being brought into line with those of men.
The committee has raised the alarm in an interim report on the New State Pension (NSP), which replaces the basic and additional state pensions from April.
The MPs said the situation was so "urgent" that they could not wait for the full inquiry to be completed before speaking out.
The said: "At a crucial time of reform to the state pension and the state pension age, Department for Work and Pensions (DWP) statements are insufficiently clear.
"This lack of clarity increases the chances that people misunderstand the value of their state pension or the age from which they will receive it. In turn, this increases the chances that they will not best plan for retirement."
The committee called for statements to be on a single page, with key messages highlighted.
The documents should clearly declare the current value of state pension built up, the age at which people will be eligible to receive the income, and how they can build up extra entitlement.