The Knot Study Finds Lab-Grown Diamonds Dominate 2026 Engagement Ring Spending

Lab-grown diamonds now dominate engagement-ring buying. The Knot Worldwide’s 2026 Real Weddings Study reports that lab-grown center stones account for 61% of all engagement ring purchases among couples married in 2025, a 239% increase since 2020, and calls the shift “The Lab-Grown Diamond Takeover.”

NEW YORK, Feb. 18, 2026. The study captured self-reported responses from 10,474 U.S. couples married between January 1 and December 31, 2025, recruited via email invitation from The Knot and WeddingWire membership throughout 2025. The Knot’s Insights & Research Team produced the report, which the company says has been fielded annually for nearly 20 years and draws on additional TKWW studies conducted in 2025.

The study places measurable consumer choices at the center of the trend. It reports that the move to lab-grown stones has coincided with larger average center-stone sizes, 1.9 ct, and lower average costs, cited as $4,600, and states that “Driven by economic pragmatism and evolving values, this shift has led to larger average carat sizes (1.9ct) and lower average costs ($4,600), [...]” The report also notes that “Nearly 9 in 10 proposers pop the question with a ring in hand,” underscoring continued demand for traditional proposal rituals even as buyers change what they buy.

Beyond the ring market, the 2026 Real Weddings Study lists broader wedding-industry themes. The press material frames its findings as drawing on “more than 10,000 U.S. couples married in 2025” and says the Study “underscores key themes such as the resiliency of the $100 billion U.S. wedding industry, how wedding planning has entered the AI era, the need for trust and personalization in selecting a dream team of wedding professionals, how Gen Z is redefining celebrations, and the takeover of lab-grown diamonds.” The report’s table of contents runs from “Key Findings” through “The 2026 Wedding Forecast,” reflecting a full-year dataset and supplemental TKWW research.

The Real Weddings Study includes next-gen planning data that intersects with the lab-grown story. Raw excerpts show that “71% of couples prioritize the advice of friends and family when planning their day,” and the report’s Gen Z lines note that 32% include religious, ethnic, or cultural elements and 28% include eco-friendly or sustainable options in their weddings, signaling values that help explain some buyers’ movement to lab-grown stones.

Readers and industry professionals should note caveats flagged in the study packet. The S3-hosted PDF excerpt truncates the sentence after the $4,600 figure and contains an unaligned social-platform table; the full study is the source for question wording, margin-of-error, and whether the $4,600 average applies to total ring spend or to center-stone expenditures. Still, with a 61% share of purchases and a 239% increase since 2020, The Knot’s numbers mark a rapid market realignment that jewelers, manufacturers, and suppliers must reckon with as inventory, pricing, and marketing adjust to a predominantly lab-grown engagement-ring market.