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Starting today, when Portland Airbnb hosts login to their account, they'll be presented with two options: Input a number associated with their city permit to operate a short-term rental—or apply for one.

After years of back-and-forth with the City of Portland, Airbnb will be requiring their Portland hosts have a Short Term Rental (STR) permit, a piece of documentation that the city made mandatory in 2014.

To obtain this permit, which applies to anyone renting out their home through Airbnb, HomeAway, VRBO, or other STR platforms, rental spaces must pass a basic safety check (conducted by the city) and hosts must pay a permit fee (which can cost up to $196) and notify their neighbors.

Hosts are also required to occupy their rental residence for at least nine months out of the year. (This rule was created to protect affordable rental homes from being turned into year-round short-term rental pads, further shrinking Portland's diminishing affordable housing supply.)

The city's been largely unable to enforce these regulations because Airbnb—the largest short-term rental provider in Portland—has refused to share data on the location of their host's rentals with the city, keeping inspectors from knowing who may be in violation. At the same time, Airbnb hasn't required its hosts obtain a STR permit before operating in Portland.

A 2018 audit by the City of Portland estimated that only 22 percent of Portland's short-term rental hosts were operating with the mandatory STR permit.

In August, after unsuccessfully trying to obtain Airbnb host data through a subpoena, the City of Portland agreed upon a 'memorandum of understanding' with the company. In the memo, Airbnb agreed to begin sharing data on its hosts (with the hosts' approval) and requiring all hosts obtain a STR permit before renting out their space. In return, the city would let Airbnb hosts fill out the permit application on the Airbnb website—instead of dealing with the city's clunkier system.

Airbnb hosts now have until December 31 to apply for a STR permit. After that point, any Airbnb listings without a permit will be removed from the website.

In October, the city published a follow-up to its 2018 audit of the STR program, which showed little improvement to the unenforceable system. "Once the data sharing and revised registration process is in place," the audit read. "Portland should have information it needs to enforce the short-term rental market."

With that process now in place, Portland might finally be able to pull back the curtain on its mysterious STR market.