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Leaving a job can make a small 401(k) hard to hold on to: Some employers ' plans cash out accounts under $1,000 or move slightly larger balances into an IRA. Taking the money in cash and moving on can feel like the simplest option, but it can have short- and long-term financial consequences.

A system backed by major 401(k) administrators aims to make it easier for those savings to follow workers to their next job. New research from one of those companies, Vanguard, shows it's helping fewer people cash out — although most of the money has yet to reach workers' new retirement plans.

Among workers with less than $1,000 in their 401(k), the share who cashed out within 10 months of leaving their job fell to about 9% from roughly 50% after their employers began participating in a new system called the Portability Services Network, according to the Vanguard research .…