Alongside the buy-back, the group said £900 million will be spent on debt reduction and £500 million on bolt-on acquisitions, confirming figures released in March.
Chief executive Mark Wilson said: “Aviva has significant surplus cash and capital and we are deploying £2 billion productively in 2018.
“The £600 million buy-back, together with our plan to repay £900 million of expensive debt maturing this year and invest in bolt-on acquisitions, will grow Aviva’s earnings, strengthen cashflow and improve debt ratios.”
The move comes a day after Aviva pledged to make a £14 million “goodwill payment” to shareholders who lost out when it cancelled £450 million worth of preference shares, before the insurance giant carried out a U-turn on the plans.
The group said on Monday that it recognises the “uncertainty” created for preference shareholders and the impact the move had on its reputation, saying the payout is the “right thing” to do.
The goodwill payment will apply to those who sold preference shares between March 8 and March 22.
The FTSE 100 insurer believes fewer than 2,000 individual investors were affected.
The original proposal had drawn criticism from investors and the FCA, although Aviva said it had received legal advice that it could cancel its preference shares at par value.
Aviva employs 2,000 people at its life and general insurance business in York and 1,500 at its life and health insurance operation in Sheffield.