It is the seventh time in eight years that the North East water firm has topped British Water′s annual list for supplier satisfaction.
Each year, the survey measures suppliers′ views on how the main water and sewerage companies perform and compare with each other.
It looks at ten different performance areas, including contract procurement, contractual approach, impact on the supply chain and communication.
Northumbrian Water came out on top, with an average overall score of 7.7 out of 10. It also scored the highest in nine out of ten of the categories.
Stephen Whaley, Northumbrian Water Group′s Contracts Procurement Manager, said: "This is another great result with suppliers choosing us as the number one water company to work for again.
"It demonstrates the hard work that we have put into building strong, working relationships with our suppliers in order to deliver an excellent service to our customers."
British Water, the trade association for the UK water industry supply chain, represents the industry collectively to government, regulators, other institutions, customers and the media.
The Northumbrian Water suppliers who take part in the survey, range from framework capital contractors and consultants, to chemicals suppliers, distribution materials suppliers, maintenance, waste and operational contractors.
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Northumbrian Water Limited supplies 2.7 million customers in the North East with both water and sewerage services, trading as Northumbrian Water, and 1.8 million customers in the South East with water services, trading as Essex & Suffolk Water.
In 2017 Northumbrian Water was named Utility of the Year at the Utility Week Awards, for the second time in four years. The company has followed this up in 2018 by winning the UK Excellence Award at the British Quality Foundation (BQF) UK Excellence Awards, and Water Company of the Year at the Water Industry Achievement Awards. Northumbrian Water also received the Queen’s Award for Enterprise for sustainable development for a second time in 2014, which is accredited for five years. This recognises the company as a business which benefits the environment, society and the economy.
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