News of the deal emerged over the weekend, with the tie-up between the companies creating a combined group that will run over £660bn in assets.
Branding of the combined group will incorporate both the Standard Life and Aberdeen names.
The merger is expected to result in cost savings of £200m a year, and reports suggest up to 1,000 jobs could be at risk.
Under the terms of the deal, Standard Life shareholders will own two-thirds of the combined group, with Aberdeen shareholders owning a third.
Standard Life chairman Sir Gerry Grimstone will become chairman of the merged company, with Aberdeen chairman Simon Troughton becoming deputy chairman.
Standard Life chief executive Keith Skeoch and Aberdeen chief executive Martin Gilbert will run the combined business.
Aberdeen’s Bill Rattray will become chief financial officer while Standard Life’s Rod Paris will become chief investment officer.