The report showed that Sir Martin earned £2.13m last year, compared with £1.59m in 2002. This is broken down to reveal he earned a basic salary of £840,000 in 2003, received a cash bonus of £1.26m and £25,000 worth of benefits including healthcare and life assurance.
It has also been revealed that Sir Martin owns more than £90m of shares in WPP, which he founded.
These latest figures come a month after a controversial pay plan was cleared by shareholders at an extraordinary general meeting. This could result in WPP's top 19 executives receiving around £112.5m, depending on company performance compared with rivals such as Omnicom Group and Interpublic Group.
The Association of British Insurers had given a "red top" warning about the plan but changed it to amber after assurances from WPP. Criticisms of the plan included accusations that WPP failed to consult properly, something that was denied by the firm.
Last week, investors in media and research firm Aegis rejected chief executive Doug Flynn's two-year contract as 52.4% of shareholders failed to back the group's remuneration report at its annual meeting.
The WPP annual report also gives confirmation that Sir Martin has bowed to shareholder pressure and abandoned his rolling three-year contract. It is expected that once his existing deal ends next year he will have a contract with a notice period of no more than a year.
Last month, WPP reported a first-quarter revenue rise of nearly 6%, including a 12% rise in the UK.
Meanwhile, it has also emerged today that Sir Martin is to join the London 2012 campaign as a "bid ambassador". Recently appointed chairman of the bid, Lord Coe, is expected to make other senior changes this week with an increased role for bid vice-chairman and ITV chief executive Charles Allen being considered.
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