Lockdown parties hosted in properties booked via online sites, including Airbnb and Booking.com, are putting “communities at risk”, the Bed and Breakfast Association has said.
Hosts and residents have complained of groups of up to 30 breaking social-distancing rules and taking drugs.
BBC News has been told of several such parties in the past month.
Airbnb said it had gone further than its rivals to protect public health during the pandemic.
However, last week a man was stabbed at a party in a south London property police believe had been rented out via the platform.
Following a previous BBC News investigation into “coronavirus retreats”, Airbnb had told users they could make bookings only if they were key workers or required “essential stays”.
But that restriction is to be lifted, in line with local rules on hotels and self-catering accommodation, in:
Rival platform Booking.com does not currently flag such limits.
“While B&Bs and guest houses have been closed since 23 March, it seems these giant platforms have allowed bookings to be made and enabled the so-called ‘lockdown parties’, which have put guests, hosts, neighbours and communities at risk,” Bed and Breakfast Association chairman David Weston said.
“It is about time these global platforms took some responsibility for the safety of their guests, their accommodation and showed some respect for local communities.”
Although the BBC saw evidence that some of the bookings involved were made via Airbnb, the hosts involved asked that their details not be shared with the company.
As a result, the platform said it had seen no evidence to connect the incidents with its business.
“We have zero tolerance for illegal activity and Airbnb is the only platform to limit all UK bookings to essential travel for key workers until restrictions are lifted,” the company said.
“We also explicitly ban party houses and our neighbourhood support tool enables anyone to contact us with concerns about a listing in their community, and we take action on issues brought to our attention.”
Booking.com did not respond to a request for comment.
Darya Simanovich, who runs Chelsea Creperie but rents out a property on both Airbnb and Booking.com for extra income, said it had been “trashed” many times since lockdown began, at the end of March, by guests posing as key workers, who had turned out to be organising illegal parties.
“I wasn’t able to meet the guest because of restrictions,” she said of one instance.
“The key collection was contact-free.
“But because I live above the property, I saw lots of people going in, with music playing.
“So I had to ask them to leave.
“Letting out your home is all about trust.
“It’s hard to think people are breaking the rules, especially when hosts have lost income.
“I don’t think the new guidelines will change anything.
“People will still bend the rules.”
Danial Abbas, who also hosts a flat on both platforms, said a group of more than 10 people held a party there until 04:00 BST last week.
“I’ve had no problems at all until lockdown,” he said.
“It’s disappointing that people would flout the rules and create disruption at a time when people are already feeling unnerved.
“I’m sad that they’ve created an extra risk.”
Another host, who asked to remain anonymous, had a group of younger adults partying in her property.
“They’re less at risk,” she said.
“They feel hard done by, as lockdown measures are largely for older people.
“They feel like they’re missing out, so don’t care if they break the rules.”
Next month, people in England are allowed to meet indoors in groups of up to two households.
But there is concern this will be difficult to enforce in short-term lets.
“The guidance as it stands is unenforceable,” Holiday Home Association chief executive Martin Sach said.
“It’s too complicated and not law.
“So self-catering owners aren’t able to police this.
“You can’t verify the relationship of your guests.”
Merilee Karr, who chairs the UK Short Term Accommodation Association, which represents short-term rental businesses, including Airbnb, said people should have made bookings only if they had legitimate reasons to do so, such as being a key worker or needing hospital treatment.
“We have been vigilant and very strict about taking bookings during lockdown and have openly opposed anyone breaching the guidelines,” she said.
“We totally disapprove of anyone that has falsely booked accommodation to hold an activity that falls outside of the government guidelines and take action where this would be discovered.”
A neighbour to a rental property, who asked to remain anonymous, told BBC News: “I live in a quiet area in London.
“But since the lockdown, and in the last four weeks, there have been four parties in my street.
“You can spot them right away.
“They only stay for one night, arrive in groups of up to 20 people, coming in and out of the house.
“I’ve been kept up all night by the loud music that has played until 05:00.
“And you can see and smell evidence of drug-taking.
“When it happens, I’ve wanted to knock on the door and confront them.
“But I have no idea who these people are, which can be scary and threatening, especially when we aren’t meant to be in crowds.
“It’s happening because people don’t have anywhere else to go at the moment.
“And they want to drink and socialise.
“Action needs to be taken.
“It’s not right to have a party house in the middle of a residential area, especially during a pandemic.”