Total equity allocations rose to 53.6 percent of all 401(k) assets, from 49 percent in March, Hewitt said in its monthly report.
International funds received 20.7 percent of all inflows in June, or $63.7 million, while lifecycle funds received 19.5 percent, or $60.2 million.
Stable-value funds experienced the most outflows for the month, with $250 million. That represented 82.8 percent of all outflows.
According to Hewitt, 23.4 percent of participant-only contributions went into stable-value funds, while 21.9 percent went into lifestyle funds, and 16.9 percent into large-cap U.S. equity funds.
For overall contributions, 21.6 percent were invested in stable value, 21.3 percent were invested in lifestyle funds, and 15.6 percent moved into large-cap U.S. equity funds.