The gains are the result of planned increases in workplace pension contributions in April, which will see them climb from 2% to 5% of salary.
The surge could see average earners adding £36,000 more to their retirement nest eggs over their lifetime, the pensions giant said.
Since 2012, auto-enrolment has introduced 9.3m more employees to saving for retirement and Aviva’s data highlights that rising contribution rates will see those on average £26,572 salaries adding £840 to their pot across 2018 - up from £600 last year.
The rise to 5% would typically see employees contributing 3% and their employer putting in the other 2%.
Pension pots are set to increase further still, with minimum contributions set to go up in April 2019 to 8%, meaning average savers would have £101,000 at retirement, representing an additional £35,000 in their pension pot and more than triple the amount they would have under current contribution levels, Aviva predicts.
Andy Curran, MD corporate at Aviva, said: “Auto-enrolment has been an incredible force for good since its introduction in 2012 with more people than ever before now contributing on a monthly basis towards their retirement.
“It is vital the latest milestone is used as a basis on which to build further momentum around the need for people to save for retirement. If as a society we are to avoid a retirement savings crunch further down the line, we must go further still in the years to come.”