Short answer. The rate-lock effect has cut U.S. existing-home active listings from a normal 1.6–1.8 million units to roughly 1.0 million in 2024 — even as buyer demand has cooled. Sellers with sub-5% mortgages are unwilling to surrender them by selling.
| Year | Existing Home Sales | Active Inventory | Months Supply |
|---|---|---|---|
| 2019 | 5.34M | ~1.5M | ~3.3 mo |
| 2021 | 6.12M | ~1.1M | ~1.8 mo |
| 2022 | 5.03M | ~1.0M | ~2.4 mo |
| 2023 | 4.09M | ~1.0M | ~2.9 mo |
| 2024 | ~4.06M | ~1.1M | ~3.2 mo |
The rate-lock effect describes the disincentive to sell facing the roughly two-thirds of U.S. mortgage holders whose existing rate sits below the prevailing market rate. The effect's measurable impact on inventory has been the defining feature of the 2022–2024 housing market.
The pre-pandemic baseline
Active U.S. listings ran consistently in the 1.6–1.8 million unit range from roughly 2014 through 2019. The figure was already low by post-2008 standards (the 2007 peak was 4.0M+) but was not unusual by long-run norms.
The post-2021 collapse
Active listings fell sharply through 2020–2022 and have remained suppressed:
- Late 2019: ~1.6M active listings
- Mid-2022 trough: under 700K — the deepest absolute low on record
- 2024 average: ~1.0M — well below the long-run norm
The 2024 reading is striking because it persists despite buyer demand having softened materially. In a normal market, weaker demand would produce rising inventory as listings accumulate. In the rate-lock era, listings are not appearing in the first place.
The arithmetic of staying put
A homeowner who bought a $400,000 home in 2021 financed $320,000 at 2.96% — a $1,344 monthly P&I. Selling and buying a similar replacement home at unchanged price but 6.84% rates produces a $2,090 P&I — $746/month more for an identical home. The rate-lock penalty for that household is roughly $9,000/year for the first year, declining over time as the new mortgage amortizes. Most households declining a job opportunity, downsize, or retirement-relocation move would have to accept this penalty.
What share of the mortgage stock is locked in?
By balance, as of late 2024:
- ~84% of mortgage debt below 6%
- ~63% below 5%
- ~22% below 3%
The 22% sub-3% cohort is essentially fixed in place at any market rate above 4%. The full rate-lock era explainer walks through how this resolves.
Implications for buyers and sellers
For buyers, the inventory shortage has kept prices firm even as transaction volume collapsed — the supply-demand imbalance acts on the price side as much as the volume side. For sellers who do list, the buyer pool is smaller but the competition for any listed property is meaningfully higher than in pre-pandemic years. The dynamics have produced a market where prices stay sticky and volume stays low simultaneously — a pattern with few clean precedents in U.S. housing history.
Related
- Housing inventory dashboard
- Q&A — What is the rate-lock effect?
- Q&A — What share of mortgages are below 5%?
- Q&A — Lowest existing home sales year
- The Rate-Lock Era, 2022–Present
Sources
U.S. Census Bureau Survey of Construction; National Association of Realtors Existing Home Sales report; Freddie Mac Primary Mortgage Market Survey; National Bureau of Economic Research Business Cycle Dating Committee.