Cheil China will be China Unicom's main branding and marketing strategy partner for 2017 and 2018.
The undertaking comes after a November pitch involving more than 20 local and multinational agencies based in Beijing, of which 11 were shortlisted for the final presentation.
Cheil did work for the telecom operator on a project basis since 2011, while JWT Beijing was its incumbent creative agency from 2013 to 2016.
Annual billings for this sought-after account are believed to be RMB 6 million (US$872,587)*.
Cheil will now be tasked to come up with a "multi-dimensional strategy to elevate brand positioning though public awareness campaigns for both B2B and B2C audiences", according to vice president of Cheil China, Vanessa Ding (丁晓宁).
By the end of 2016, China Unicom had 273 million subscribers, among which, broadband subscribers totalled 30 million, GSM subscribers 133 million and fixed-line (including PHS) subscribers 109 million.
* We originally published an incorrect figure for this estimate.