The former ANZ Queen St branch is set to become a pharmacy and homewares shop.
Co-owners Jason Wright and Stuart Hebberd, who run Prices 7 Day Pharmacy in Nelson, are behind the business.
It is due to open in mid-October and will create eight jobs.
The Marlborough Express understands there is opposition to the new business and a meeting of chemists will be held on Monday night. Blenheim already has eight pharmacies.
Hebberd defended the decision to move to Blenheim, saying there was demand.
"I feel there is room in the market for another pharmacy. In Nelson we have had two pharmacies open up within 100 yards of us and it hasn't hurt our business."
Three pharmacists contacted in Blenheim did not wish to comment on the new business.
Hebberd said Prices already dispensed prepackaged medicine dosages into individual sachets to three rest homes in Blenheim.
A robotic packaging system had given it an edge and meant it could produce up to 10 different sachet doses a day for a patient, much more than rival systems.
It was more accurate and saved rest homes nurse time.
A physical presence in Blenheim would boost their pharmaceutical service, Hebberd said.
The outlet, which is yet to be named, will be divided into a pharmacy and a homewares department.
Hebberd said they had applied for a dispensing contract with the Nelson and Marlborough District Health Board and the application was being processed.
The Queen St building has been vacant since June when ANZ's Queen and Market street branches merged, and now operate out of the heritage National Bank building in Market St.
- The Marlborough Express
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