It might seem like a good idea to sneak a few bits of extra rubbish or recycling into your neighbour's bin on collection day, but Auckland Council warns it is illegal.

The warning comes after Auckland Barfoot & Thompson real estate agents Matt O'Brien and Cris Casares' latest marketing ploy that involved pasting flyers to the inside lid of recycling bins.

The flyers suggested neighbours' bins were full of champagne bottles due to them celebrating the selling of their property.

"The house we just sold down the road has Champagne bottles in their recycle bin," the flyer says.

"When you want top dollar for your home call Matt O'Brien or Cris Casares."

The marketing flyers, which picture empty Champagne bottles, drew some criticism from Auckland residents.

One homeowner took to Twitter to respond to the unwanted junk mail: "Can't believe I have to say this but AUCKLAND REALTORS STAY OUT OF MY BIN!!!!!!"

Another said: "Thought they were trying to hint that our bins were too rowdy."

Others said the flyers were "inappropriate" and to call the estate agents to "come and collect this trash".

"Oh wow. That's next level marketing," another Twitter user wrote. "Research opportunity in analysing houses sold with champers bottles in recycling? What's the price premium? You can do the data collection!"

can’t believe I have to say this but AUCKLAND REALTORS STAY OUT OF MY BIN!!!!!! pic.twitter.com/YArwUdkC7E

— Katie (@k_tieparker) October 19, 2018

While the council ultimately owned the bins, they were the responsibility of the property owner.

Auckland Council waste enterprises and refuse manager Terry Coe said placing items into another person's bin was a bylaw breach under the Auckland Council Solid Waste Bylaw 2012. Breaches could result in prosecution.

"If you have concerns someone is dumping illegally into your bin, we encourage you to contact us immediately so that our waste team can investigate," Coe said.

The council does not receive many complaints of this nature, receiving four this year.

Barfoot & Thompson had since stopped distributing the flyers.

"The majority see the posters, attached to the inner lid of recycle bins, for what they are – a tongue-in-cheek promotion. However, there is a bylaw prohibiting putting material into other people's recycle and rubbish bins and the act of attaching the posters will be viewed by some as interfering with their property," Barfoot & Thompson managing director Peter Thompson told Stuff.

"I give Christina and Matt full marks for trying, but it is a step too far. What needs to be emphasised, is that the agents did not enter people's properties. The leaflets were attached when the bins were at the kerb following recycling."

Real Estate Institute of NZ chief executive Bindi Norwell said the marketing ploy was clearly a case of when an attempt to be innovative missed the mark.

She also confirmed with the agents that the leaflets had only been placed into bins that were on the kerb and that no one entered private property.

"We also understand that the agents involved won't be continuing with the promotion."

Advertising Standards Authority chief executive Hilary Souter said her body could investigate the flyers if they received a complaint.

However, because the agents had agreed to stop distributing the flyers, the authority would likely consider the case settled.