A new state law could mean more homes for sale on sites like Zillow, Redfin or Realtor.com.

Starting in October, most residential sales must be advertised publicly – unless the seller explicitly opts out.

The new law aims to protect sellers from losing money – and shield buyers from housing discrimination.

If you’re house-hunting, you know how tight the market is right now.

“There’s multiple buyers and it is just really tough to get the house that you want,” said homeowner Mike Slaven.

Making things even worse? Some homes aren’t even advertised to the general public. They’re called “private” or “pocket” listings.

“'Pocket listings' are meant to be kept quiet and off-market,” said Christopher Halstead, Connecticut sales director for Brown Harris Stevens in Westport.

Some brokers promote secret listings – marketed to a select group of agents on private listing networks, or to a broker within the same agency – as a faster way to sell one's house or reach a specific buyer pool.

But a study from Zillow found that private sales cost the average seller $4,230, or 1.3% less than homes listed on the Multiple Listing Service.

“The only person who benefits in a ‘pocket listing’ scenario is the agent and the broker,” he said.

“Pocket listings” can also shut out minorities and less wealthy buyers.

“Prospective buyers and tenants, including those using housing vouchers, may never have the opportunity to make an offer on a property for sale or lease simply because they were unaware it was available,” said Jim Heckman, general counsel for the Connecticut Realtors, which represents 18,000 agents across the state.

A new state law may change that. Starting on Oct. 1, residential properties under four units must be publicly advertised – unless the seller signs an opt-out form disclosing the financial risks.

State Sen. Tony Hwang (R-Fairfield), who sponsored the legislation, said some sellers have no idea their listings were hidden.

“This is an opportunity to increase transparency,” he said. “You can always agree to have it outside of the MLS, but you need to know about it now. And opt out of it through a form signature.”

Realtors who violate the new law face a $5,000 fine and could also lose their real estate license.

Gov. Ned Lamont signed the law last week. In New York, a similar bill is awaiting Gov. Kathy Hochul’s signature. Illinois and Hawaii are considering similar proposals, while Washington state prohibits “pocket listings” altogether.

In Connecticut, the new law doesn’t ban private listings. In fact, in some situations, realtors say that keeping a listing secret makes sense.

“A divorce scenario where people don’t want that information out in the public,” Halstead said. “Or, you know, somebody that is in the public eye.”

Will the new law actually mean more home listings? Or will sellers continue to opt for secret sales?

“I don’t know what kind of impact that’s going to have,” Slaven said. “I think it’ll actually make it easier for buyers. They’ll see more product.”