The company said it was asked by the regulator to identify whether its customers received "sufficient information" during this period.
On Friday, the FCA said it would order a number of firms to review their annuity sales back to 2008 after finding evidence of “concerns”.
Officials found “particularly poor behaviour” at a small number of firms, which may face enforcement action. But they found no widespread “systemic” problems.
Standard Life released a statement, explaining it had been a participant in the FCA review.
It said: “At the request of the FCA, Standard Life will conduct a review of all non-advised annuity sales from July 2008 to identify whether our customers received sufficient information about enhanced annuities to make the right decisions about their purchase.
“It is not yet possible to determine a reliable estimate of the quantum of any redress associated with this process.”
Standard Life added: “Our Annual Report and Accounts 2015 noted a contingent liability in light of the potential for a requirement to compensate customers flowing from the FCA's review. It is possible that the financial impact may be mitigated by our group professional indemnity insurance.”
The FCA examined whether firms made customers aware of their potential eligibility for enhanced annuities and whether they encouraged them to shop around in order to potentially get a higher income from another provider.
The FCA has asked all annuity providers to consider whether they can make improvements to the annuity sale process.
The regulator says that up to 90,000 consumers may have been sold a standard annuity when they could have qualified for an enhanced annuity. As a result up to £240 a year may have been lost by consumers in the affected cases and compensation may be required.
At a “small number of firms” it had concerns when significant communications took place orally – usually by phone – which was “likely to have caused some customers to purchase a standard annuity when they may have been eligible for an enhanced product.”
The FCA said: “These failings were of sufficient concern at a small number of firms that they are now being asked by the FCA to review all non-advised sales from July 2008 and, where appropriate, provide redress; these firms are also being investigated by the FCA’s Enforcement Division to determine whether further action is necessary.”
The review was set up by the FCA to establish whether firms provided customers with sufficient information about enhanced annuities. The FCA looked at whether firms made customers aware of their potential eligibility for enhanced annuities and whether they encouraged them to shop around.
The FCA reviewed non-advised sales of annuities made by pension providers to their customers between May 2008 and April 2015.
The FCA looked at the information provided in respect of enhanced (impaired life) annuities. The FCA review looked at more than 1200 non-advised sales at seven firms which between them account for approximately two-thirds of the annuity market.
The FCA found “no evidence” of an industry-wide or systemic failure to provide customers with sufficient information about enhanced annuities through non-advised sales. The FCA found many of the firms provided clear and comprehensive information to customers with written communication tending to meet the standards required.