Sir Edward had maintained that the omission was due to a misunderstanding. But the Standards and Privileges Committee said he had ignored clear advice from Sir Gordon Downey, the former Parliamentary Commissioner for Standards.
The former Tory premier had reacted angrily to reports in The Independent on Sunday and The Independent that he had held undeclared paid posts with six organisations. He said there was no need to register the interests because he did not believe they would influence his actions, speeches or parliamentary votes.
Sir Edward was an adviser to the China Ocean Shipping Company, Dresdner Kleinwort Benson, Arthur Andersen and the Praemium Imperiale Tokyo arts awards. He also sat on the governing board of the Centre for Global Energy Studies and was international patron to the Varkey International Academy in Dubai.
The committee decided to take no further action against him, noting that he had expressed regret. But it added: "The advice given by the then commissioner leaves the committee in no doubt that Sir Edward had been told that the rules required him to register his interests. Members should pay attention to the commissioner's advice."
Sir Edward said in a statement that he had withdrawn the advisory posts from the register as a result of a "misunderstanding" over the effect of a rule change.
"As has been made clear, I regret the misunderstanding," he said. "I have sought and am seeking neither to undermine the rules nor to win special treatment for myself."
Sir Edward had declared the advisory posts but withdrew them from his entry in the 1996 register - the first to be drawn up under the new rules in response to the report of Lord Nolan's Committee on Standards in Public Life.
In his reply to the complaint, Sir Edward - who had been a leading critic of the Nolan reforms - said none of his interests had affected his actions as an MP and he had never raised them in the House or contacted ministers about them.
Sir Edward has now reinstated the entry, adding a new post with Jardine Fleming, and omitting the Varkey Academy and Dresdner Kleinwort Benson because his arrangements with them have ended.