Diana Garbutt's body was discovered in March in her flat above Melsonby's village store and post office, which she ran with her husband, Robin.
She died from head injuries, and her husband has been charged with her murder and will stand trial next year.
Post Office Limited has confirmed that a temporary mobile service will start on January 4 and will be overseen by the subpostmaster of Bedale Post Office.
A mobile post office will be parked on Aldbrough Road on Tuesdays from 2.30pm until 4.30pm and on Wednesdays between 1.30pm and 3.30pm.
Post Office Limited's field change adviser, Gillian Alstead, said: "We will continue to work hard towards finding a long-term sustainable solution for service provision in Melsonby.
"Meanwhile, this mobile service will enable customers to access Post Office products and services over the coming months."
Garbutt, 45, denies killing his 40-year-old wife, whose body was found in their home above Melsonby Post Office on March 23.
He is due to face trial at Teesside Crown Court in March next year.
The discovery of Mrs Garbutt's body in the village to the north of Richmond sparked a massive manhunt by North Yorkshire Police.
Detectives launched a murder investigation and initially issued a description of a robber who had reportedly broken into the post office and stolen a substantial amount of cash.
However, Garbutt was arrested by officers on April 14 and then charged with his wife's murder.