Agency Adjustable-Rate Mortgage Market Share

Agency ARMs represent 3.34% of reported 2026 YTD agency originations by loan count, up from 0.31% in full-year 2021. The chart therefore shows roughly a 10× increase in product penetration, not a 10× increase in total ARM production. Reported ARM loan counts were 35,591 in 2021 and 39,166 in 2026 YTD, while total market loan counts shown were 11.6 million and 1.17 million, respectively.

For a geographic view of the trend, see ARM penetration by state.

For lenders, the strategic signal is that ARMs have become materially more relevant within the agency product mix. Product, pricing and capital-markets teams can use the share trend to assess whether ARM offerings, rate sheets, investor outlets, hedging assumptions and sales training remain aligned with market composition. Production leaders can also benchmark their own ARM share against the market rather than compare raw counts across unequal periods. See the agency ARM refinance lender rankings for a lender-level view of the market.

Because 2021 covers a full year and 2026 is year-to-date, the absolute loan counts provide context rather than a direct growth comparison. Market share is the more useful measure for evaluating the change in ARM penetration across the two periods.