The housing rush is fueled by the pandemic and the desire of people who can work remotely to get out of the city.
Homebuilders are passing the costs of delays on to consumers because demand for houses is so high.
The National Association of Realtors says it has more members than the number of homes for sale at the moment.
But they are still very low, historically speaking. Here's what that could mean for the housing market.
An increase in the cost of new homes then drives up the price of existing homes, as the overall market becomes more competitive.
Some of what we're seeing might be making up for a spring in which people were stuck at home and not buying.
The numbers suggest that the reopening of major parts of the country gave a boost to the housing market.
Demand is still outstripping housing supply.