Centrelink says a huge surge of complaints from its customers last year came after the welfare agency made it easier for clients to express their unhappiness.

But critics say the long-term trend of dissatisfied customers tells the story of an organisation in crisis.

Graph of Centrelink complaints 2011-2016 produced by http://iscentrelinkdown.com Credit:IsCentreLinkDown.com

Nearly 114,000 complaints surged into Centrelink in the 2015-2016 financial year, but only 6000 compliments and another 6000 'suggestions'.

The number of complaints is nearly double that of the previous year, when 62,000 messages were received from unhappy customers.