The hosepipe ban has been extended to include more of Cornwall and much of Devon as the region continues to experience lower levels of rainfall.
South West Water said its actions were put in place to "break the cycle of drought".
This comes as reservoir levels fell to their lowest-ever recorded levels last year with some water supplies already lower than this previous record.
South West Water says it hopes to lift the Cornwall and Devon hosepipe sooner if "drought-breaking rainfall" takes place
The company said it hoped the hosepipe ban would be lifted by December 1 "or sooner" if the two areas saw "drought-breaking rainfall".
In a statement to customers on its website, South West Water said: "Our water resources across the region remain under pressure and as we go into the summer period we have taken the necessary action to safeguard supplies and break the cycle of drought following lower than average levels of rainfall last year and throughout February."
How to see if there is a hosepipe ban in my areas: Check your postcode
If you're struggling to find out if you are affected by the hosepipe ban then there are handy tools to help you out.
Water UK has introduced a postcode checker to help UK residents find out if they are affected by the ban on using a hosepipe.
Simply enter a valid UK postcode and the website will do the rest.
On its website, Water UK says: "If you are a household customer, you can check who provides your water and sewerage services by entering your postcode."
Find out more by visiting the Water UK website.
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