In a year that saw a more than 6% decline for overall single-family housing starts, custom home building posted a gain. The custom building market is less sensitive to the interest rate cycle than other forms of home building but is more sensitive to changes in household wealth and stock prices. With spec home building down and the stock market up, custom building expanded its market share. According to NAHB’s analysis of Census data from the Quarterly Starts and Completions by Purpose and Design survey, there were 45,000 total custom building starts during the fourth quarter of 2025. This is down 4% relative to the fourth quarter of 2024. However, for 2025 as a whole, custom single-family housing starts totaled 186,000 homes, a 3% increase compared to 2024 (181,000). Currently, the market share of custom home building, based on a one-year moving average, is almost 20% of total single-family starts.