Banks Sadler, Capita Travel and Events, CWT Meetings and Events, George P Johnson, Ashfield Meetings & Events, WRG, Zibrant, TBA and Chillisauce also made the top ten.
The Top 20 UK Agencies table is ranked by event-based turnover and agencies were asked to provide this figure, along with total UK turnover and pre-tax profit, for their most recent financial year, as reported to Companies House.
For agencies that have already filed their 2015 results with Companies House, these figures have been verified by C&IT. All other figures are based on agencies' estimates of what they expect to report.
New entries in this year's Top 20 list include TBA, cievents, BI Worldwide and Smyle Group.
In addition to the top 20 by event-based turnover, C&IT will be publishing a top 20 table featuring turnover with client billings or total client spend, which will be revealed tomorrow.
The secondary ranking is designed to give an idea of total client spend put through the top UK agencies, which gives insight into the value of the industry.
The full Top 50 list, ranked by events-based turnover, will be revealed next week.
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