Nearly three in 10 high-net-worth investors in the U.S. consider themselves “self directed,” according to a new report by Cerulli Associates.

For the financial-market research firm, this helps explain a “surge” in HNW investors’ use of online brokers — a trend augmented, Cerulli’s Donnie Ethier says in a press release, by the channel’s improved HNW capabilities in recent years and their favor with “younger, tech-savvy wealth creators.”

For this reason, adds Ethier, discount brokers “represent increasingly worthy competitors” to traditional wealth managers. Cerulli says more than 50% of HNW investors have online trading-account balances of between $500,000 and $1 million.

Overall, however, “the self-directed model becomes less favorable relative to other advice models as assets increase” and portfolios become more complex, says Ethier.

Meanwhile, Cerulli figures asset managers should view “direct providers” as “yet another avenue” for getting their wares in front of big-money individual investors.

By Cerulli’s reckoning, a high-net-worth investor has at least $5 million in investable assets. Its measure of an ultra-high-net-worth investor starts at $20 million.