Canadian Blood Services says it will stop collecting blood in Torbay, Mount Pearl and the Goulds neighbourhood of St. John's.
Officials argue not enough people have been using the mobile clinics in those communities, so they will close in May and June.
"They're currently not performing to the collection targets," said Peter MacDonald, director of donor relations for Atlantic Canada.
The clinics in Torbay and Goulds have been collecting 30-32 units of blood, below the goal of 38 units.
MacDonald said the larger clinic in Mount Pearl also hasn't been meeting it's target of 58 units.
Staff have been visiting those communities between four and six times a year, and the clinics only run for four hours.
"For some folks it would be more convenient if the mobile was coming to Torbay, the Goulds or Mount Pearl, but those donors, we're hoping, we'll be able to convert them to the Wicklow Street site," said MacDonald.
The blood agency operates a permanent clinic at that building five days a week, and recently expanded hours to include Saturday clinics.
MacDonald said there won't be any reduction in staff as part of the clinic cuts.
Not expecting drop in donations
Canadian Blood Services frequently makes appeals for more donors to avoid blood shortages.
Recently the agency said it would need an extra 35,000 donations a year nationally because women will now have to wait 12 weeks between donations instead of eight weeks.
MacDonald insists shutting down three clinics won't lead to less blood collected.
He said the focus on more convenient hours at permanent clinics is part of a trend across the country, and will appeal to more donors.
The Newfoundland and Labrador health minister was informed of the change in a confidential briefing note in February.
In that note, obtained by CBC News through access to information, it said this is part of a national plan with "increased focus on permanent locations in metropolitan areas."
Staff advised the minister that there will be no change to how hospitals receive blood.