Employee vs. Employer Contributions
Employee contributions to a 401(k) are always 100% vested and divisible by QDRO. The more complicated issue is with employer contributions. Typically, these vest based on a schedule (e.g., 25% after 2 years, 100% after 5 years). The alternate payee is usually only entitled to the vested portion of employer contributions at the time of divorce or plan division — not anything unvested.
That means timing matters. If the employee spouse is close to full vesting, it might make sense to delay the QDRO submission until they’re fully vested. Otherwise, the alternate payee could lose out on unvested amounts that would later become 100% vested to the employee spouse post-divorce.

