(NewsNation) — Switching jobs is one of the best ways to boost your income, but new research suggests it can also hurt your retirement savings if you’re not paying attention.

That’s because many job switchers get auto-enrolled in 401(k) plans at a lower savings rate at their new employer, according to Vanguard.

Voluntary retirement plans, which require employees to sign up on their own, can also dampen savings, with many job switchers failing to opt in even if they were contributing at their last job.

The study found that the typical job switcher sees a 10% increase in pay but a 0.7 percentage point decline in their retirement saving rate when they switch employers.

The savings slowdown means a worker earning $60,000 a year at the start of their career who switches jobs eight times could have as much as $300,000 less in retirement savings, Vanguard found. That’s enough to fund roughly six additional years of spending in retirement.

The 401(k) is a popular retirement savings plan that allows employees to contribute a portion of their salary to an individual account — and employers will often match up to a certain amount. However, the new analysis suggests workers should pay extra attention when switching jobs since plans vary from employer to employer.

For workers who are automatically enrolled in their company’s 401(k), about 60% stick to their plan’s default savings rate, with 3% being the most common. These “passive savers” were more likely to see a reduction in their savings rate after changing jobs, Vanguard found, whereas “active savers” who chose their own savings rate fared better.

Vanguard recommends saving 12% to 15% each year for retirement, significantly more than the most popular 3% default contribution rate.

Job tenure also matters, especially for passive savers. Vanguard found that workers who spent longer at their previous employer experienced a larger reduction in retirement savings when switching jobs.

That’s because many plans gradually increase the savings rate over time. So if someone switches jobs and doesn’t change their rate, it effectively resets at their new employer, which could take several years to bring back up.

Many job switchers, about 60% in the sample, joined companies with automatic enrollment, and they experienced a smaller savings decline than those who joined a voluntary enrollment plan. In fact, Vanguard found that roughly a quarter of workers who transitioned to voluntary enrollment plans didn’t continue saving at all.

The report’s findings show that those who rely on 401(k) default rates could be missing out on major savings.

The study is based on 54,793 job switchers from 1,059 employers and includes only those job switchers who joined their new company within one year of leaving their previous jobs.