The annual water deadline is rapidly approaching. For those Murrumbidgee customers looking to trade excess water interstate, the deadline to do so will be 11:59pm on April 30.

Alternatively, those wishing to trade within the Murrumbidgee area will have until 11:59pm on May 31.

Under stipulation of the state's Water Sharing Plan, licence holders will be at risk of forfeiting excess if unused by the expiration.

Those subscribing to the use of both regulated and unregulated water, including groundwater, will have until June 30 to make the necessary provisions.

Customers may have already received correspondence from WaterNSW notifying them of their options as the water year comes to a conclusion.

WaterNSW executive manager of customer and community, David Stockler, said it was a matter of reminding users of their rights and responsibilities in accordance with the rules.

"We are acting to ensure customers are aware of the potential implications," Mr Stockler said.

"This approach reflects our commitment to continuing to enhance our levels of service and striving to make it easier for our customers as they go about running their businesses."

Water fees are determined by the Independent Pricing and Regulatory Tribunal, and are current for the period between July 1, 2018 and June 30, 2019.

An annual fee increase is expected, based on changes to the consumer price index.

The trading of water, especially interstate, is subject to a variety of party approvals.

Licence holders are required to submit an application to WaterNSW ahead of delivery.

Applications may be accessed by visiting https://www.waternsw.com.au/customer-service/ordering-trading-and-pricing/trading.

More information can be accessed via the WaterNSW helpdesk on 1300 662 077.