The majority of the remaining markets, in New Zealand and internationally, are for plastics stamped with the number 1 or 2.
Waste Futures Committee chairwoman Tania Kerr said the council needed the community's help.
"We are disappointed to be in this position but given the ever-decreasing number of markets for used plastic, at this time we have no choice," Kerr said.
"We want residents to be assured that we are continuing to look for ways to have our plastics recycled while also backing moves at a national level to reduce problem plastics, and encouraging people to try to buy products in plastics that can be recycled."
Up until March this year, Hastings' contractor had not had to send any of its collected plastics to the landfill or stockpile it.
"Hastings' contractors have a good record of finding markets for our recycling but in order for that to continue there must be changes," Kerr said.
"To do that, we cannot mix non-recyclable plastics with those that can be recycled.
"Mixing plastics will result in all of the recycling potentially having to go to the landfill which is the worst outcome, both environmentally and financially."
Kerr said consumers could have an impact by shopping wisely, such as choosing recyclable clear and opaque bottles when shopping, and checking the recycling grade as well.
"Check the bottoms of your containers when you buy. If we all make these small changes, together we can make very big differences."
The changes also affect drop-off recycling stations.
