The collapse of U.S. investment bank Lehman Brothers in September 2008 plunged the global financial system into chaos and its European arm, based in London, was the largest and most complex part of the group because it was a hub for trading and investments spanning asset classes and dozens of countries.
The administrators have recovered money by unwinding derivatives contracts and share trades, and winning several legal battles over other parts of the former bank.
Lomas said the full payout of claims showed regulators and central banks developing plans to prevent a repeat of the financial crisis need to make sure banks have enough liquidity to withstand a crisis, and not just focus on capital strength.
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"In times of distress customers panic and want their money or assets back, so in a major, complex financial institution the liquidity needs will be as significant as the balance sheet needs," Lomas said.
PwC is expected to return about £40 billion in total to LBIE's creditors, including near £23 billion for trust claimants and about £16 billion for up to 3,400 unsecured creditors.
Surplus cash could be paid later this year if creditors agree to a proposal to be made soon made by PwC, which will propose a split based on interest payments, foreign exchange moves and the claims of subordinated debt holders. Unsecured creditors can get 8 percent interest a year under UK law.
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