Introduction to the World Survey 2021

Dear readers,

Welcome to the free summary of the International Accounting Bulletin 2021 World Survey.

The IAB has an established reputation, built up over decades, for ranking and providing insight on the work of global accounting networks and associations.

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Key findings World Survey 2021

The IAB surveyed 52 organisations this year, comprising of 30 networks and 22 associations, earning a combined $241.4bn in fee income – up slightly from $234.5bn the previous year.

Average growth amongst networks in 2021 was 3%. The Big Four’s combined revenue increased by 1.5%, down from 4% in 2019, while the mid-tier networks combined revenues increased by 6% year on year. For associations the growth was only 2% in 2020, which is down from 14% in 2019.

In the top 20 networks, HLB, Mazars, ETL Global, SFAI and Russel Bedford International saw strong double-digit growth rates. Of the 30 participating networks, only 5 saw decreases in revenue in 2020.

Across audit, performance was slow with networks seeing a small 1% increase in fee income to $71bn, while for associations fee incomes in audit overall were flat, with combined fee income just under $9.3bn. It was a better year for tax as networks grew the service line by 3% and associations by 10%. Similarly, fee income increased by 4% for networks in advisory to $76.6bn, and 8% for associations to $5.4bn.

Staff growth was more sluggish in the past year, with networks growing their staff base by 4% and associations by 3% (7% and 8% respectively in 2019).

Total revenue vs growth: 2003-2020

Revenue $bn


Notes: Growth = the average growth of networks and associations surveyed.

Source: International Accounting Bulletin