Hutt Valley District Health Board says the ending of overnight service at a medical clinic will put a strain on Hutt Hospital.
From next month, the only after-hours clinic in Lower Hutt will stop the 11pm - 7am service because only four patients on average use it.
Those wanting to see a doctor after 11pm will need to be seen at Hutt Hospital.
The DHB says it's working on a plan to cope with the extra patients.
A new emergency department is being built at the hospital.