The firm said it intends to focus on residential customers and is looking to sell off its non-household retail division.
The division is currently based in Bradford and Barnsley.
A spokesman for the company said it was "early days" in the process, adding that it was important to keep staff informed.
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He added that about 100 staff were directly involved in the non-household retail business at sites in Bradford and Barnsley.
Yorkshire Water currently has about 138,000 business customers.
Yorkshire Water has announced plans to sell off its business supply division, with 100 jobs potentially at risk.